Mookaite from the Cretaceous of Western Australia. (~6.75 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

Mookaite from the Cretaceous of Western Australia. (~6.75 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

Chert is a cryptocrystalline, quartzose sedimentary rock. It principally forms as a chemical sedimentary rock (for example, diagenetic chert nodules) or as a biogenic sedimentary rock (for example, bedded radiolarian cherts). "Flint" is a synonymous term that is asserted by some to be distinctive from chert. Flintknappers will say that chert is low-quality (= low-purity?) and flint is high-quality (= high-purity?), in terms of making tools such as arrowheads. The British will say that flint is biogenic in origin and that chert is chemical in origin. Some will say that chert is light-colored and flint is dark-colored. Regardless, chert and flint are the same - they're both cryptocrystalline, quartzose sedimentary rocks. Chert / flint is hard, has conchoidal fracture (smooth & curved fracture surfaces), and sharp broken edges.

Locality: farmer's field between the towns of Utica and Mount Vernon, southern Knox County, central Ohio, USA

Mookaite from the Cretaceous of Western Australia. (~6.75 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

Mookaite from the Cretaceous of Western Australia. (~6.35 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

Market Hill, with what used to be the Co-op on the left. The new buildings on the right are on the site of what was a carpark.

Mookaite from the Cretaceous of Western Australia. (~6.6 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

Mookaite from the Cretaceous of Western Australia. (~5.55 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

This Suffolk pub was a meeting place for bikers, and sadly closed in March 2011

Mookaite from the Cretaceous of Western Australia. (~5.55 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

Mookaite from the Cretaceous of Western Australia. (~10.1 centimeters across at its widest)

Mookaite is a silicified sedimentary rock from the Lower Cretaceous Windalia Radiolarite Formation, a succession of moderately deep marine siltstones and cherts that contain numerous microfossils of foraminifera, radiolarians, and coccoliths. Because this rock is hard, very fine-grained, and attractively colored, mookaite is valued as knapping material by flintknappers.

The yellowish and reddish colors are from iron oxide impurities (limonite and hematite).

In archaeology, a lithic flake is a "portion of rock removed from an objective piece by percussion or pressure,"[1] and may also be referred to as a chip or spall, or collectively as debitage. The objective piece, or the rock being reduced by the removal of flakes, is known as a core.[2] Once the proper tool stone has been selected, a percussor or pressure flaker (e.g. an antler tine) is used to direct a sharp blow, or apply sufficient force, respectively, to the surface of the stone, often on the edge of the piece. The energy of this blow propagates through the material, often (but not always) producing a Hertzian cone of force which causes the rock to fracture in a controllable fashion. Since cores are often struck on an edge with a suitable angle (x<90°) for flake propagation, the result is that only a portion of the Hertzian cone is created. The process continues as the flintknapper detaches the desired number of flakes from the core, which is marked with the negative scars of these removals. The surface area of the core which received the blows necessary for detaching the flakes is referred to as the striking platform. From Wikipedia, the free encyclopedia

Chert from the Mississippian of Indiana, USA. (~9.95 centimeters across at its widest)

This rock is "Indiana hornstone". If correctly attributed, it is a chert nodule derived from a Mississippian-aged limestone unit in southern Indiana - likely Harrison County or Crawford County.

Chert is a cryptocrystalline, quartzose sedimentary rock. It consists of tiny quartz crystals too small to see with normal microscopes ("crypto" means "hidden").

In this sample, the dark-colored material is unaltered chert (referred to by some as "flint"). The light-colored material is a weathering rind, which is called "cortex" by flintknappers.

Early American Indians used Indiana hornstone to make arrowheads, spearpoints, and other stone tools.

Locality: unrecorded/undisclosed site in Indiana (possibly southern Indiana), USA

Expert flintknapper, Michael Miller, demonstrates his craft to our visitors.

Photo by: Taylor H. Thornton

Expert flintknapper, Michael Miller, demonstrates his craft to our visitors.

Photo by: Taylor H. Thornton

Viking Festival 2015

Expert flintknapper, Michael Miller, demonstrates his craft to our visitors.

Photo by: Taylor H. Thornton

Chert is a cryptocrystalline, quartzose sedimentary rock. It principally forms as a chemical sedimentary rock (for example, diagenetic chert nodules) or as a biogenic sedimentary rock (for example, bedded radiolarian cherts). "Flint" is a synonymous term that is asserted by some to be distinctive from chert. Flintknappers will say that chert is low-quality (= low-purity?) and flint is high-quality (= high-purity?), in terms of making tools such as arrowheads. The British will say that flint is biogenic in origin and that chert is chemical in origin. Some will say that chert is light-colored and flint is dark-colored. Regardless, chert and flint are the same - they're both cryptocrystalline, quartzose sedimentary rocks. Chert / flint is hard, has conchoidal fracture (smooth & curved fracture surfaces), and sharp broken edges.

This chert sample has numerous concentric bands, similar to that seen in "pinstripe flint", or "Nethers Flint" at Flint Ridge, Ohio. The concentricity is reminiscent of "Liesegang banding" (really "Wells banding"), but that forms in porous rocks such as sandstone or conglomerate.

Locality: farmer's field between the towns of Utica and Mount Vernon, southern Knox County, central Ohio, USA

Expert flintknapper, Michael Miller, demonstrates his craft to our visitors.

Photo by: Taylor H. Thornton

One of dozens of people re-enacting old times at the Middle Earth Festival in Hall Green a couple of weeks ago. This guy looked very realistic - a cross between a stone age Briton and a Wild West backwoodsman.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

Chert from the Mississippian of Indiana, USA. (~8.7 centimeters across at its widest)

This rock is "Indiana hornstone". If correctly attributed, it is a chert nodule derived from a Mississippian-aged limestone unit in southern Indiana - likely Harrison County or Crawford County.

Chert is a cryptocrystalline, quartzose sedimentary rock. It consists of tiny quartz crystals too small to see with normal microscopes ("crypto" means "hidden").

In this sample, the dark-colored material is unaltered chert (referred to by some as "flint"). The light-colored material is a weathering rind, which is called "cortex" by flintknappers.

Early American Indians used Indiana hornstone to make arrowheads, spearpoints, and other stone tools.

Locality: unrecorded/undisclosed site in Indiana (possibly southern Indiana), USA

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

Chert from the Mississippian of Indiana, USA. (~11.1 centimeters across at its widest)

This rock is "Indiana hornstone". If correctly attributed, it is a chert nodule derived from a Mississippian-aged limestone unit in southern Indiana - likely Harrison County or Crawford County.

Chert is a cryptocrystalline, quartzose sedimentary rock. It consists of tiny quartz crystals too small to see with normal microscopes ("crypto" means "hidden").

In this sample, the dark-colored material is unaltered chert (referred to by some as "flint"). The light-colored material is a weathering rind, which is called "cortex" by flintknappers.

Early American Indians used Indiana hornstone to make arrowheads, spearpoints, and other stone tools.

Locality: unrecorded/undisclosed site in Indiana (possibly southern Indiana), USA

At obsidian dome. A flintknapper's paradise! This block probably weighs about 800 pounds, and appears to be pretty sound. You could make a lot of Folsom and Clovis points out of that! Back when I was an archaeologist, I'd have made the trip up here just to see this mountain of beautiful obsidian. This day, I almost drove past without stopping. Times change.

Flint from Thetford in Norfolk. Some of the gardens are sponsored by local authorities. This one was going to be rebuilt after the show.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

via Tumblr.

Final shape, calling this done ….In trying to learn how to #flute #clovis #paleoindian #points I have found a way to drive far far flakes on very rough limestone material, they DID make points from rock here in #newengland just as beautiful as elsewhere with better rock. It just seems to be a bit more difficult as the rock isn’t as agreeable. This is chert from upstate #newyork #flint. I am not so concerned about getting the style right as I am getting the flutes to run on this tough stuff, I think I finally figured it, flute or channel flake on the left…. Point on the right. A friend gave me some advice that seems to be right on the $. #paleo #paleolithic #archaeology #anthropology #bushcraft #outdoorsman #survival #survivalist #knife #flintknapper #crafts #primitive #limestone #paleotechnology #visionquest #caveman #flintknapping #chipping #aboriginal ift.tt/29UpMDA

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

Mountain Man Rendezvous Mountain Man Rendezvous - These Flintknappers demonstrate the art of shapping flint into arrow heads and spear heads. Their camp sites were teepees and their dress were leathers and indian style adornments.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

A flintknapper is an individual who shapes flint or other stone through the process of knapping or lithic reduction, to manufacture stone tools, strikers for flintlock firearms, or to produce flat-faced stones for building or facing walls.

Knapping is done in a variety of ways depending on the purpose of the final product. For stone tools and flintlock strikers flint is worked using a fabricator, such as a hammerstone, to remove lithic flakes from a nucleus or core of tool stone. Stone tools can then be further refined using wood, bone, and antler tools to perform pressure flaking.

For building work a hammer or pick is used to split flint nodules supported on the lap. Often the flint nodule will be split in half to create two flints with a flat circular face for use in walls constructed of lime. More sophisticated knapping is employed to produce almost perfect cubes which are used as bricks.

In cultures that have not adopted metalworking technologies, the production of stone tools by flintknappers is common, but in modern cultures the making of such tools is the domain of experimental archaeologists and hobbyists. Archaeologists usually undertake the task so that they can better understand how prehistoric stone tools were made.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

This November we celebrated everything geological as part of the Festival of Geology, in partnership with the Geologists’ Association.

We were showcasing some rare rocks, minerals and fossils from the UCL Geology Collection and Materials Library. Visitors saw meteorites that are composed of a rare type of iron not found on earth. Played with naturally magnetic sand from California. Gazed into an obsidian mirror, which has a long history of association with the supernatural. Watched master flintknapper Karl Lee make delicate tools, weapons and decorative items lump of flint.

We were also exploring the world of geological fakery with fool's gold and synthetic rubies. Visitors got the chance to see if they can spot the synthetic diamonds.

Guests made and named their very own fake rocks with prop maker Richard Graham.

People could try their hand at carving soft materials, like limestone, pumpkins, chocolate, cheese and soap; architectural stonemason Paul Jakeman was on hand to lend carving tips!

Our Makespace manager Ellie, made honeycomb rock and you could try rock! Finally Jo Lathwood was displaying her latest project, ‘Is this Magma?’ and discussing the melting points of rocks.

Chert from the Mississippian of Indiana, USA. (~5.7 centimeters across at its widest near the base)

This rock is "Indiana hornstone". If correctly attributed, it is a chert nodule derived from a Mississippian-aged limestone unit in southern Indiana - likely Harrison County or Crawford County.

Chert is a cryptocrystalline, quartzose sedimentary rock. It consists of tiny quartz crystals too small to see with normal microscopes ("crypto" means "hidden").

In this sample, the dark-colored material is unaltered chert (referred to by some as "flint"). The light-colored material is a weathering rind, which is called "cortex" by flintknappers.

Early American Indians used Indiana hornstone to make arrowheads, spearpoints, and other stone tools.

Locality: unrecorded/undisclosed site in Indiana (possibly southern Indiana), USA