Chert (Iron-stained)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Category
Organic Gemstone (Often Associated With Sedimentary Sequences)
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Prehnite with Epidote inclusions
Ca2Al(AlSi3O10)(OH)2
mineral
Chert (or Cryptocrystalline Quartz)
Silicon Dioxide (SiO2)
sedimentary
Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Amazonite (or Amazon Stone)
Potassium Feldspar (Microcline), K(AlSi3O8)
mineral
Sodalite
Na8(Al6Si6O24)Cl2
mineral
Lepidolite
K(Li,Al)3(Si,Al)4O10(F,OH)2
mineral
Pyrite
Iron Sulfide (FeS2)
mineral
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Pyrite
Iron Sulfide (FeS2)
mineral
Jasper
Silicon Dioxide (SiO2) - Microcrystalline Quartz
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Leopard Skin Jasper
Silicon Dioxide (SiO2) with impurities
sedimentary
Chert (often called Flint or Jasper based on color)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Rhodochrosite
Manganese Carbonate (MnCO3)
mineral
Petrified Wood
Silicified Wood (primarily Chalcedony/Quartz, SiO2)
fossil
Jasper (Red-Brown)
Silicon Dioxide (SiO2) with Iron Oxide impurities
sedimentary
Amber (Copal)
Organic gemstone, fossilized tree resin (often immature amber or copal)
Mineral
Milky Quartz with Mica inclusions
Quartz (Silicon Dioxide, SiO2)
mineral
Red Jasper
Jasper (Silicon Dioxide, SiO2 with iron oxide impurities)
sedimentary
Tumbled carnelian (red-orange chalcedony)
Carnelian, a microcrystalline variety of quartz (SiO₂), colored mainly by iron oxides
gemstone
Polished black stone, likely shungite
Shungite; carbon-rich mineraloid composed mainly of amorphous carbon, with silica and other minerals
mineral
Red Coral (with Hematite and Black Pearl accents)
Corallium rubrum (Calcium Carbonate, CaCO3)
mineral
Carnelian
SiO2 (Variety of Chalcedony/Quartz)
gemstone
Amber
Succinite (approximate formula C10H16O)
mineral
Amygdaloidal Basalt
Amygdaloidal Basalt
igneous
Polished amber
Fossilized tree resin (primarily organic polymerized diterpenes)
gemstone
Chert (Chalcedony)
Silicon Dioxide (SiO2)
sedimentary
Tiger's Eye
Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)
metamorphic
Chert (Flint nodule)
Chert (SiO2)
sedimentary
Beryl (var. Heliodor or Aquamarine)
Beryllium Aluminum Cyclosilicate (Be3Al2Si6O18)
mineral
Jasper
Silicon Dioxide (SiO2) with iron and magnesium inclusions
sedimentary
Amber
Succinite (Formula: C10H16O)
Mineraloid
Petrified Wood
Silicified wood (SiO2)
sedimentary
Pearls (likely freshwater cultured pearls)
Pearl: nacre, primarily aragonite (CaCO₃) with conchiolin
gemstone
Rhodonite
Manganese Silicate (Mn,Fe,Mg,Ca)SiO3
mineral
Polished amber-colored translucent stone, likely citrine or yellow chalcedony
Most consistent with quartz (SiO₂), potentially citrine; translucent yellow chalcedony is another possibility
mineral
Carnelian
Carnelian (a variety of Chalcedony, SiO ₂)
Mineral (specifically a variety of Chalcedony, which is a cryptocrystalline quartz)
Chert (Nodule)
Silicon Dioxide (SiO2)
sedimentary
Rough Emerald
Beryl (Be3Al2Si6O18 with Chromium/Vanadium impurities)
gemstone
Prehnite
Prehnite (Ca2Al2Si3O10(OH)2)
mineral