Geology (Architectural & Otherwise) of the Earth's Center, Part 8: Premium Marble On a Limestone Landscape | Delphi, Phocis, Greece
Looking westward at this small edifice's Doric facade.
The first portion of the title refers to the fact that the ancient Greeks considered Delphi the navel of the world.
In Part 7 of this set we had our first look at the Athenian Treasury from our perch atop the Theater. Here we see it close at hand, with some Almond Trees (Prunus dulcis) in full bloom, at left, behind it. This building dates to the late sixth or early fifth century BC, and its reconstruction, effected by a team of French archaeologists, was completed in AD 1906.
The Athenian Treasury is distinguished from other notable structures of the Delphi complex by the allochthonous (imported) rock type that serves as its building material.
Even from this distance, it could appear that the Treasury is made of ashlar of one of the locally derived limestones used so prolifically elsewhere on site. It could be, that is, if it weren't for its overt whiteness. Architectural limestones tend to be off-white at best, or pale gray, or bluish-gray, or buff, or even black. Note, for example, the much darker blocks of limestone-derived Slope Breccia sitting in front of the entrance.
And if you could step a little closer, and especially if you could touch this stone, you'd know by its fine- to medium-grained calcite-crystal matrix that it's actually the metamorphosed form of limestone. In other words, it's true marble.
Because this wee architectural gem is the Athenians' Delphic showplace, you'd think that its builders would have used one or both of their own splendid Pentelic and Hymettian Marbles, extracted from mountainsides just to the east of their great and powerful city. But in their quest for ostentatious one-upmanship they went one step farther, and procured the most highly esteemed marble of all, from the Cycladic isle of Paros.
Parian Marble, especially prized by ancient sculptors, was admired for its waxy and workable texture, and for its translucence. In fact, light can be perceived traveling through it to a thickness of 35 mm (1.4 in), whereas the Pentelic has a depth of translucence of only 15 mm (0.6 in). That may not be as impressive as window glass, but it certainly is a notable feat for any rock.
My source for these measurements is, incidentally, Norman Herz's "Geology of the Building Stones of Ancient Greece,” Transactions of the New York Academy of Sciences 17, 7 Series II (May 1955): 499-505.
Of course, the Parian here has gone through many centuries of weathering, discoloration, and biofilm growth. I suspect the bright-white column-drum sections are replacement units made of something else. Or maybe of more recently produced Parian? It was quarried for a while in the late nineteenth century AD, though that's no proof of its use here.
Still, I gather that the other stones, with the exception of the metopes, are all or mostly original.
Interestingly, while the literature abounds with discussion of the archaeology of ancient Paros quarries, I have not found much about the Parian Marble's geology. Pivko noted that it was metamorphosed at some point in the Tertiary, but that's about it (“Natural Stones in Earth’s History,” Acta Geologica Universitatis Comnenianae 58 (2003): 73-86).
I gather from Greek bedrock maps that the limestone protolith was either Upper Paleozoic or Mesozoic, but I can find no reference to its depositional environment.
To see the other photos and descriptions in this series, visit my Geology (Architectural & Otherwise) of the Earth's Center album.
Geology (Architectural & Otherwise) of the Earth's Center, Part 8: Premium Marble On a Limestone Landscape | Delphi, Phocis, Greece
Looking westward at this small edifice's Doric facade.
The first portion of the title refers to the fact that the ancient Greeks considered Delphi the navel of the world.
In Part 7 of this set we had our first look at the Athenian Treasury from our perch atop the Theater. Here we see it close at hand, with some Almond Trees (Prunus dulcis) in full bloom, at left, behind it. This building dates to the late sixth or early fifth century BC, and its reconstruction, effected by a team of French archaeologists, was completed in AD 1906.
The Athenian Treasury is distinguished from other notable structures of the Delphi complex by the allochthonous (imported) rock type that serves as its building material.
Even from this distance, it could appear that the Treasury is made of ashlar of one of the locally derived limestones used so prolifically elsewhere on site. It could be, that is, if it weren't for its overt whiteness. Architectural limestones tend to be off-white at best, or pale gray, or bluish-gray, or buff, or even black. Note, for example, the much darker blocks of limestone-derived Slope Breccia sitting in front of the entrance.
And if you could step a little closer, and especially if you could touch this stone, you'd know by its fine- to medium-grained calcite-crystal matrix that it's actually the metamorphosed form of limestone. In other words, it's true marble.
Because this wee architectural gem is the Athenians' Delphic showplace, you'd think that its builders would have used one or both of their own splendid Pentelic and Hymettian Marbles, extracted from mountainsides just to the east of their great and powerful city. But in their quest for ostentatious one-upmanship they went one step farther, and procured the most highly esteemed marble of all, from the Cycladic isle of Paros.
Parian Marble, especially prized by ancient sculptors, was admired for its waxy and workable texture, and for its translucence. In fact, light can be perceived traveling through it to a thickness of 35 mm (1.4 in), whereas the Pentelic has a depth of translucence of only 15 mm (0.6 in). That may not be as impressive as window glass, but it certainly is a notable feat for any rock.
My source for these measurements is, incidentally, Norman Herz's "Geology of the Building Stones of Ancient Greece,” Transactions of the New York Academy of Sciences 17, 7 Series II (May 1955): 499-505.
Of course, the Parian here has gone through many centuries of weathering, discoloration, and biofilm growth. I suspect the bright-white column-drum sections are replacement units made of something else. Or maybe of more recently produced Parian? It was quarried for a while in the late nineteenth century AD, though that's no proof of its use here.
Still, I gather that the other stones, with the exception of the metopes, are all or mostly original.
Interestingly, while the literature abounds with discussion of the archaeology of ancient Paros quarries, I have not found much about the Parian Marble's geology. Pivko noted that it was metamorphosed at some point in the Tertiary, but that's about it (“Natural Stones in Earth’s History,” Acta Geologica Universitatis Comnenianae 58 (2003): 73-86).
I gather from Greek bedrock maps that the limestone protolith was either Upper Paleozoic or Mesozoic, but I can find no reference to its depositional environment.
To see the other photos and descriptions in this series, visit my Geology (Architectural & Otherwise) of the Earth's Center album.