Crystals
Coprolite
Fossilized fecal material Trace fossil and bromalite Phosphatic, carbonate, iron-rich, or silicified Bone, scale, shell, plant, and microfossil inclusions Pellet, segmented, spiral, and irregular forms Occasionally agatized and polishable Evidence...
Coprolite
Fossilized fecal material Trace fossil and bromalite Phosphatic, carbonate, iron-rich, or silicified Bone, scale, shell, plant, and microfossil inclusions Pellet, segmented, spiral, and irregular forms Occasionally agatized and polishable Evidence...
Malachite
Copper carbonate hydroxide Cu2CO3(OH)2 Monoclinic crystal system Mohs approximately 3.5–4 Specific gravity approximately 3.6–4.0 Light-green streak Botryoidal, fibrous, stalactitic, and banded Closely associated with azurite Acid- and ammonia-sensitive Malachite: Copper’s...
Malachite
Copper carbonate hydroxide Cu2CO3(OH)2 Monoclinic crystal system Mohs approximately 3.5–4 Specific gravity approximately 3.6–4.0 Light-green streak Botryoidal, fibrous, stalactitic, and banded Closely associated with azurite Acid- and ammonia-sensitive Malachite: Copper’s...
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...