Tree Agate
Silicon Dioxide (SiO2) with Dendritic Inclusions
Category
Browse organic (paper and cellulose) specimens identified by the Rock Identifier community.
Tree Agate
Silicon Dioxide (SiO2) with Dendritic Inclusions
Petrified Wood
Silicified Wood (SiO2)
Moss Agate
Chalcedony (Silicon Dioxide, SiO2) with inclusions of Chlorite, Manganese, or Iron
Petrified Wood
Silicified Wood (SiO2)
Amber / Copal
Fossilized Tree Resin (Succinate)
Amber
Succinite (C10H16O)
Likely chert or flint
Microcrystalline quartz (SiO₂), commonly called chert; exact identification requires testing
Amber
Fossilized Tree Resin (C10H16O)
Amber
Succinite (fossilized resin)
Green Moss Agate
Silicon Dioxide (SiO2) with Mineral Inclusions
Amber
Succinurite (C10H16O)
Druzy Quartz on Vesicular Basalt
Silicon Dioxide (SiO2) in an extrusive Mafic igneous host rock
Sand Tiger Shark Tooth
Carcharias taurus
Carbonaceous Chondrite (CV3 type)
Carbonaceous Chondrite (CV3 group)
Coral Fossil (Agatized Coral or Petoskey Stone)
Hexagonaria percarinata (if Petoskey) or generally Scleractinia (Agatized Coral)
Quartzite
Quartzite (primarily SiO2)
Sandstone (Glauconitic)
Glauconitic Quartz Sandstone (SiO2 + (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2)
Chert (often called Flint)
Chert (Microcrystalline Silicon Dioxide, SiO2)
Horse Chestnut (Buckeye seed)
Aesculus hippocastanum seed
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂ - Silicon Dioxide)
Amber
Succinite (Fossilized Tree Resin)
Amber
Succinite (C10H16O)
Lignite (Brown Coal)
Humic Lignite (Carbonaceous sedimentary rock)
Amber
Succinates (Organic Fossilized Resin)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified Wood (primarily SiO₂)
Shale or Slaty Mudstone
Argillaceous sedimentary rock
Chalk
Calcium Carbonate (CaCO3)
Ferruginous Quartz
Silicon Dioxide (SiO2) with Hematite/Limonite impurities
Fossiliferous Limestone / Fossil Fragment
Calcium Carbonate (CaCO3) with indeterminate biogenic remains
Petrified Wood
Silicified Wood (primarily SiO2 - Silicon Dioxide)
Petrified Wood
Silicified Wood (SiO2)
Petrified Wood
Silicified wood (primarily SiO2)
Pearl
Organic gemstone (Calcium carbonate - CaCO3)
Petrified Wood
Silicified Wood (primarily SiO2)
Fossilized Bone (Petrified Bone)
Permineralized Vertebrate Remains
Pearl
Organic Mineral (CaCO3 with conchiolin)
Petrified Wood
Silicified wood (primarily Silicon Dioxide, SiO2)
Chert (Nodule)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
Precious Coral
Corallium rubrum (Calcium Carbonate, CaCO3)