Polished carnelian
Carnelian, a chalcedony variety of microcrystalline quartz (SiO₂), colored mainly by iron oxides
gemstone
Category
Organic Gemstone (Often Associated With Sedimentary Sequences)
Browse organic gemstone (often associated with sedimentary sequences) specimens identified by the Rock Identifier community.
Learn about Organic Gemstone (Often Associated With Sedimentary Sequences) in the encyclopedia
View all →
Yellow Sapphire
Corundum (Al2O3)
gemstone
Chert (Flint)
Chert (Microcrystalline Quartz, SiO2)
sedimentary
Chert (Flint)
Microcrystalline Quartz (SiO2)
sedimentary
Iron-rich concretion or weathered ironstone pebble
Goethite/limonite-bearing ironstone; commonly an iron-oxide concretion (FeO(OH)·nH₂O, variable)
sedimentary
Banded chert or silicified limestone nodule
Microcrystalline quartz (SiO₂), possibly replacing carbonate fossils
sedimentary
Quartz (specifically Milky/White Quartz)
Silicon Dioxide (SiO2)
mineral
Rhodonite
(Mn,Fe,Mg,Ca)SiO3
mineral
Chert (Black Chert/Flint)
Microcrystalline quartz (SiO2)
sedimentary
Fluorite
Calcium Fluoride (CaF2)
mineral
Red Jasper
Silicon Dioxide with Iron Oxide impurities (SiO2 + Fe2O3)
Mineral (variety of Chalcedony/Quartz)
Red Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Yellow Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Jasper (Brown Iron-Rich Variety)
Silicon Dioxide (SiO2) with Fe2O3 (Iron Oxide/Crystalline Quartz)
sedimentary
Amber (Copal)
Succinite (fossilized resin)
mineral
Chrysocolla
Chrysocolla, (Cu, Al)2H2Si2O5(OH)4·nH2O
mineral
Chert (Agatized/Chalcedony variety)
Microcrystalline Quartz (SiO2)
sedimentary
Tumbled carnelian
Carnelian, a reddish-orange variety of chalcedony (microcrystalline quartz, SiO₂), colored mainly by iron oxides
gemstone
White quartz-rich metamorphic rock, likely quartzite
Quartzite; predominantly crystalline SiO₂, possibly micaceous or feldspathic
metamorphic
Chert (often called Flint or Jasper)
Silicon Dioxide (SiO2)
sedimentary
Chert (specifically Red Chert or Jasper)
Microcrystalline Quartz (SiO2)
sedimentary
Moss Agate
Silicon Dioxide with inclusions (SiO2 + Mn/Fe oxides)
mineral
Lepidolite
Lepidolite (K(Li,Al)3(Al,Si,Rb)4O10(F,OH)2)
mineral
Indian Agate
Silicon Dioxide (Chalcedony), SiO2
sedimentary
Malachite
Copper(II) carbonate hydroxide, Cu2CO3(OH)2
mineral
Epidote with Quartz
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
metamorphic
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Silicon dioxide (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Celestite
Celestine (SrSO4)
mineral
Fluorite
Calcium Fluoride (CaF2)
mineral
Polished moss agate
Moss agate, a variety of chalcedony (microcrystalline quartz, SiO₂)
gemstone
Chert (Flint)
Cryptocrystalline quartz (SiO2)
sedimentary
Tumbled chert or flint
Microcrystalline quartz (SiO₂), likely brown chert/flint
sedimentary
Chert (Jasper variation)
Microcrystalline Quartz (SiO2)
sedimentary
Amber
Succinite (a fossilized organic resin)
mineral
Prehnite
Prehnite (Ca2Al(AlSi3O10)(OH)2)
mineral
Pyrite Nodule
Iron Sulfide (FeS2)
mineral
Jasper (Imperial Jasper style)
Silicon Dioxide (SiO2) with impurities
sedimentary
Chert / Flint
Cryptocrystalline Quartz (SiO2)
sedimentary
Beaded Jewelry (Assorted Gemstones)
Various minerals, including but not limited to Quartz (SiO2), Garnet (X3Y2(SiO4)3), Jade (Na(Al,Fe)Si2O6), Amethyst (SiO2),等の多様な組み合わせ
Mineral, Jewelry