Crystals
Larimar
Blue variety of pectolite NaCa2Si3O8(OH) Triclinic crystal system Mohs approximately 4.5–5 Radiating fibrous aggregates Sky, lagoon, and blue-green tones Hydrothermal veins in volcanic rock Barahona, Dominican Republic Larimar: Dominican Blue...
Larimar
Blue variety of pectolite NaCa2Si3O8(OH) Triclinic crystal system Mohs approximately 4.5–5 Radiating fibrous aggregates Sky, lagoon, and blue-green tones Hydrothermal veins in volcanic rock Barahona, Dominican Republic Larimar: Dominican Blue...
Jade
Umbrella term for two gem materials Jadeite: NaAlSi2O6 Nephrite: Ca2(Mg,Fe)5Si8O22(OH)2 Both monoclinic Jadeite Mohs approximately 6.5–7 Nephrite Mohs approximately 6–6.5 Exceptional resistance to breakage Green, white, lavender, yellow, red-brown, and...
Jade
Umbrella term for two gem materials Jadeite: NaAlSi2O6 Nephrite: Ca2(Mg,Fe)5Si8O22(OH)2 Both monoclinic Jadeite Mohs approximately 6.5–7 Nephrite Mohs approximately 6–6.5 Exceptional resistance to breakage Green, white, lavender, yellow, red-brown, and...
Emerald
Green variety of beryl Be3Al2Si6O18 Hexagonal crystal system Mohs approximately 7.5–8 Chromium and/or vanadium color Jardin inclusions and fissures Rare six-spoked trapiche growth Clarity enhancement commonly disclosed Emerald: The Green...
Emerald
Green variety of beryl Be3Al2Si6O18 Hexagonal crystal system Mohs approximately 7.5–8 Chromium and/or vanadium color Jardin inclusions and fissures Rare six-spoked trapiche growth Clarity enhancement commonly disclosed Emerald: The Green...
Copper
Native-element metal Cu Atomic number 29 Isometric crystal system Face-centered cubic structure Mohs approximately 2.5–3 Specific gravity approximately 8.96 Brown, black, green, and blue patinas Natural copper–silver intergrowths Commonly associated...
Copper
Native-element metal Cu Atomic number 29 Isometric crystal system Face-centered cubic structure Mohs approximately 2.5–3 Specific gravity approximately 8.96 Brown, black, green, and blue patinas Natural copper–silver intergrowths Commonly associated...
Amber
Fossil resin Organic gem rather than a mineral Amorphous polymeric material Mohs approximately 2–2.5 Specific gravity approximately 1.05–1.10 Plant, fungal, and arthropod inclusions Variable fluorescence Natural, heated, clarified, pressed, or...
Amber
Fossil resin Organic gem rather than a mineral Amorphous polymeric material Mohs approximately 2–2.5 Specific gravity approximately 1.05–1.10 Plant, fungal, and arthropod inclusions Variable fluorescence Natural, heated, clarified, pressed, or...
Onyx
Banded chalcedony SiO2 Parallel black-and-white layers Sardonyx: brown-red and pale bands Mohs approximately 6.5–7 Waxy to vitreous luster Classic cameo and intaglio material Commercial black material is often treated Distinct...
Onyx
Banded chalcedony SiO2 Parallel black-and-white layers Sardonyx: brown-red and pale bands Mohs approximately 6.5–7 Waxy to vitreous luster Classic cameo and intaglio material Commercial black material is often treated Distinct...