Chert / Flint (a variety of Chert)
Chert (SiO2)
Sedimentary Rock (technically a microcrystalline quartz mineral aggregate)
Category
The Purple Specimen Is A Mineral (Amethyst); The White Specimen Is A Sedimentary Rock (Limestone Or Marble).
Browse the purple specimen is a mineral (amethyst); the white specimen is a sedimentary rock (limestone or marble). specimens identified by the Rock Identifier community.
River Pebble (Siltstone/Mudstone)
Clastic sedimentary rock
sedimentary
Jasper (Multi-color Chert)
Silicon dioxide (SiO2)
sedimentary
Milky Quartz
Quartz (SiO2) with iron staining
mineral
Sandstone Concretion
Moqui Marble / Ironstone Concretion (Iron oxide-cemented sandstone)
sedimentary
Yellow Quartz (Citrine appearance)
Silicon Dioxide (SiO2)
mineral
Green Calcite
Calcium Carbonate (CaCO3)
mineral
Chert (often called Flint when dark)
Microcrystalline or Cryptocrystalline Quartz (SiO2)
sedimentary
Quartzite (clastic/metamorphic subtype)
Quartzite (primarily Silicon Dioxide, SiO2)
metamorphic
Chert (Flint)
Chert (SiO2)
sedimentary
Red Jasper
Jasper (Silicon Dioxide, SiO2 with Iron Oxide impurities)
sedimentary
Banded Agate (specifically Botswana Agate or Water-line Agate)
Chalcedony (cryptocrystalline variety of Quartz), SiO2
mineral
Jasper with Quartz inclusions
Silicon Dioxide (SiO2) - Microcrystalline Chalcedony
sedimentary
Clear Quartz Crystal (Herkimer Diamond style)
Silicon Dioxide (SiO2)
mineral
Chert / Flint
Microcrystalline Quartz (SiO2)
sedimentary
Quartz Geode
Silicon Dioxide (SiO2)
mineral
Rose Quartz
Silicon Dioxide with traces of titanium, iron, or manganese (SiO2)
mineral
Shale (sub-type: Carbonaceous Shale)
Lutaceous Sedimentary Rock
sedimentary
Chert (Jasper variety)
Silicon Dioxide (SiO2)
sedimentary
Quartz (Crystalline Cluster)
Silicon Dioxide (SiO2)
mineral
Yellow Quartz (Citrine Quartz or Yellow Chalcedony)
Silicon Dioxide (SiO2)
mineral
Chert with Desert Varnish
Cryptocrystalline Quartz (SiO2) with Manganese/Iron oxide coating
sedimentary
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Chert (and Fossilized Brachiopod shell)
Sedimentary Cryptocrystalline Quartz (SiO2)
sedimentary
Jasper (River pebble)
Jasper / Silicon Dioxide (SiO2)
sedimentary
Limonite and Goethite encrusted Chert/Ironstone
Hydrated Iron Oxide (FeO(OH)·nH2O) with cryptocrystalline Silica (SiO2)
sedimentary
Rough Green Calcite
Calcite (Calcium Carbonate, CaCO3)
mineral
Siltstone Pebble
Siltstone (fine-grained siliciclastic sedimentary rock)
sedimentary
Fossiliferous Limestone with Rugose Coral
Calcite (CaCO3) containing a Rugosa (Horn Coral) fossil
sedimentary
Apatite
Fluorapatite (Ca5(PO4)3F)
mineral
Bivalve Fossil (Internal Mold)
Class Bivalvia (Phylum Mollusca)
sedimentary
Amethyst (Tumbled Quartz)
Silicon Dioxide (SiO2) with iron impurities
mineral
Jasper
Jasper (Silicate - SiO2)
sedimentary
Fossilized Solitary Rugose Coral (Horn Coral)
Order: Rugosa (e.g., Grewingkia or Heliophyllum); composed of Calcite (CaCO3) or Silica (SiO2)
sedimentary
Quartz with Iron Oxide Monzonite or Sandstone contact
Quartz (SiO2) with Limonite/Hematite staining
mineral
Sandstone (with Liesegang rings or Oxidation)
Arenite (primarily Quartz SiO2 with Iron Oxide Fe2O3 staining)
sedimentary
Red Jasper with Quartz Veining
Silicon Dioxide (SiO2) - Microcrystalline Quartz with Iron Oxide impurities (Hematite)
sedimentary
Clear Quartz (Rock Crystal)
Silicon Dioxide (SiO2)
mineral
Basalt Porphyry
Porphyritic Basalt
igneous
Geode (unopened)
Quartz-filled Geode (SiO2)
sedimentary
Grey River Stone (Quartz-rich Quartzite/Siltstone)
Quartzite / Meta-siltstone (primarily SiO2)
Metamorphic (low-grade)
Basalt (with possible quartz veinsing)
Basalt
igneous