The light within a stone
These two polished stones are composed of lapis lazuli. Under incandescent or sun light, they appear a deep blue color with paler areas and speckles of golden pyrite, among other impurities. Under ultraviolet light, these pale areas glow a bright yellow. Those areas are made of calcite, a common inclusion and in the mineral which gives off this bright yellow light from within the stone.
These two samples suggest to me lightning flashes as seen from space. This mineral has a long and fascinating history. Each specimen is unique and very beautiful, often more so by the impurities they contain. They are sort of like us, don't you think?
For more information, read on.
lapis lazuli (UK: /ˌlæpɪs ˈlæz(j)ʊli, ˈlæʒʊ-, -ˌli, -ˌlʌɪ/; US: /ˈlæz(j)əli, ˈlæʒə-, -ˌliˌ læˈzuːli/) is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color. Its name originates from the Persian word for the gem, lāžward, and serves as the root for the word for "blue" in several languages, including Spanish and Portuguese azul and English azure. Lapis lazuli is a rock composed primarily of the minerals lazurite, pyrite, diopside, and calcite. As early as the 7th millennium BC, lapis lazuli was mined in the Sar-i Sang mines, and in other mines in Badakhshan province in modern northeast Afghanistan. Lapis lazuli artifacts, dated to 7570 BC, have been found at Bhirrana, which is the oldest site of Indus Valley Civilization. Lapis was highly valued by the Indus Valley Civilization (3300–1900 BC). Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, and as far away as Mauritania. It was used in the funeral mask of Tutankhamun (1341–1323 BC).
By the end of the Middle Ages, Europe began importing lapis lazuli to grind it into powder and make ultramarine pigment. Ultramarine was used by some of the most important artists of the Renaissance and Baroque, including Masaccio, Perugino, Titian and Vermeer; it was often reserved for the clothing of the central figures of their paintings, especially the Virgin Mary. Ultramarine has also been found in dental tartar of medieval nuns and scribes, perhaps as a result of licking their painting brushes while producing medieval texts and manuscripts.
The light within a stone
These two polished stones are composed of lapis lazuli. Under incandescent or sun light, they appear a deep blue color with paler areas and speckles of golden pyrite, among other impurities. Under ultraviolet light, these pale areas glow a bright yellow. Those areas are made of calcite, a common inclusion and in the mineral which gives off this bright yellow light from within the stone.
These two samples suggest to me lightning flashes as seen from space. This mineral has a long and fascinating history. Each specimen is unique and very beautiful, often more so by the impurities they contain. They are sort of like us, don't you think?
For more information, read on.
lapis lazuli (UK: /ˌlæpɪs ˈlæz(j)ʊli, ˈlæʒʊ-, -ˌli, -ˌlʌɪ/; US: /ˈlæz(j)əli, ˈlæʒə-, -ˌliˌ læˈzuːli/) is a deep-blue metamorphic rock used as a semi-precious stone that has been prized since antiquity for its intense color. Its name originates from the Persian word for the gem, lāžward, and serves as the root for the word for "blue" in several languages, including Spanish and Portuguese azul and English azure. Lapis lazuli is a rock composed primarily of the minerals lazurite, pyrite, diopside, and calcite. As early as the 7th millennium BC, lapis lazuli was mined in the Sar-i Sang mines, and in other mines in Badakhshan province in modern northeast Afghanistan. Lapis lazuli artifacts, dated to 7570 BC, have been found at Bhirrana, which is the oldest site of Indus Valley Civilization. Lapis was highly valued by the Indus Valley Civilization (3300–1900 BC). Lapis beads have been found at Neolithic burials in Mehrgarh, the Caucasus, and as far away as Mauritania. It was used in the funeral mask of Tutankhamun (1341–1323 BC).
By the end of the Middle Ages, Europe began importing lapis lazuli to grind it into powder and make ultramarine pigment. Ultramarine was used by some of the most important artists of the Renaissance and Baroque, including Masaccio, Perugino, Titian and Vermeer; it was often reserved for the clothing of the central figures of their paintings, especially the Virgin Mary. Ultramarine has also been found in dental tartar of medieval nuns and scribes, perhaps as a result of licking their painting brushes while producing medieval texts and manuscripts.