Moss Agate
Chalcedony with inclusions
mineral
Category
Organic Gemstone (Not A Rock Or Mineral)
Browse organic gemstone (not a rock or mineral) specimens identified by the Rock Identifier community.
Learn about Organic Gemstone (Not A Rock Or Mineral) in the encyclopedia
View all →
Red Jasper
SiO2 (Silicon Dioxide with Hematite inclusions)
mineral
Tiger's Eye
Silicon dioxide (SiO2) - Pseudomorph after crocidolite
mineral
Fire Opal (in Matrix)
Hydrated Silica (SiO2·nH2O)
mineral
Milky Quartz Nodule / Geode precursor
Silicon Dioxide (SiO2)
mineral
Pearl
Calcium Carbonate (mostly Aragonite), CaCO3 (with conchiolin)
mineral
Rough Amethyst
Silicon Dioxide (SiO2) with iron impurities
mineral
Carnelian and White Quartz Bracelet
Silicon Dioxide (SiO2) - specifically Carnelian (Chalcedony) and Rock Crystal/Snow Quartz
mineral
Epidote
Epidote (Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH))
mineral
Pink Coral
Corallium rubrum (or related species, composed of calcium carbonate)
gemstone
Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Amber
Succinite (C10H16O)
mineraloid
Chert Nodule
Chert (Microcrystalline Silicon Dioxide, SiO2)
sedimentary
Unakite
Epidotized Granite
metamorphic
Petrified Wood
Silicified Wood (primarily Chalcedony or Quartz, SiO2)
sedimentary
White Topaz
Aluminum Silicate Fluoride Hydroxide; Al2SiO4(F,OH)2
mineral
Petrified Wood
Silicified Wood (SiO2)
sedimentary
Geode Nodules / Keokuk Geode
Quartz / Chalcedony Geode (SiO2)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
sedimentary
Chert (Jasper/Flint variety)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartz
Silicon Dioxide (SiO2)
mineral
Jasper
Silicon dioxide (SiO2)
sedimentary
Amber (likely raw amber)
Fossilized tree resin; organic mineraloid, commonly containing succinite (not a true mineral)
gemstone
Aquamarine
Beryl (Be3Al2Si6O18)
gemstone
Amber
Succinate (Fossilized Tree Resin)
mineraloid
Blue Quartzite (Dyed)
Metamorphosed Quartz-rich Sandstone (SiO2 with organic dye)
metamorphic
Fossiliferous Limestone (Shell Fragment)
Biogenic Limestone (Calcium Carbonate / CaCO3)
sedimentary
Banded Chert
Microcrystalline Quartz (SiO2)
sedimentary
Sandstone (Red / Iron-stained)
Sandstone (composed predominantly of SiO2 with Fe2O3 cement)
sedimentary
Likely rough blue-gray kyanite
Kyanite, Al₂SiO₅
mineral
Quartz fragment
Quartz (silicon dioxide, SiO₂)
mineral
Limestone with Fossil Fragments
Bioclastic Carbonate Rock (CaCO3)
sedimentary
Petrified Wood (Black / Carbonized)
Silicon Dioxide (Quartz/Chalcedony replacing Organic Matter)
fossil
Turquoise (likely stabilized or composite)
Turquoise, hydrated copper aluminum phosphate — CuAl₆(PO₄)₄(OH)₈·4H₂O
gemstone
Fossil Coral
Phylum Cnidaria / Rugosa or Tabulata
fossil
Turquoise in Matrix
Hydrous phosphate of copper and aluminium, CuAl6(PO4)4(OH)8·4H2O
mineral
Small pale mineral fragment
Indeterminate; possibly quartz or calcite
mineral
Chert
Chert (SiO2)
sedimentary
Chert / Flint
Chert (Silicon Dioxide, SiO2)
sedimentary
Petrified Wood
Silicified Paleoxylon (SiO2)
fossil
Amber
Succinite (specifically for Baltic Amber), Formula: C10H16O
Organic Gemstone (often associated with Sedimentary sequences)