White Topaz
Aluminum silicate fluoride hydroxide (Al2SiO4(F,OH)2)
mineral
Category
Mineral, Often A Rock Given Its Aggregate Nature
Browse mineral, often a rock given its aggregate nature specimens identified by the Rock Identifier community.
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Gossan (with Limonite/Hematite coating)
Ferruginous Gossan (Fe2O3·nH2O / Fe2O3)
sedimentary
Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Silicon (Industrial Grade)
Elemental Silicon (Si)
mineral
Basalt (Weathered River Pebble)
Extrusive Igneous Rock
igneous
Basalt Pebble
Extrusive Igneous Rock
igneous
Greywacke (Sandstone)
Lithic wacke
sedimentary
Basalt
Extrusive Igneous Rock (Mafic)
igneous
Granite
Intrusive Igneous Rock
igneous
Quartz (Rock Crystal) with minor impurities
Quartz (SiO2)
Mineral
Given the appearance, it's likely a fragment of an igneous or metamorphic rock composed of multiple minerals. Without specific diagnostic features, it's difficult to give a common name other than 'crystalline rock fragment'. If pressed to guess based on the granular, somewhat light and dark speckled appearance, it could be a fragment of granite or a related intrusive igneous rock.
As a rock fragment, it does not have a single scientific mineral name; rather, it's a piece of a rock which is a combination of minerals. If it were granite, its main mineral composition would be quartz (SiO2), feldspar (e.g., KAlSi3O8 - orthoclase, (Na,Ca)(Al,Si)4O8 - plagioclase), and mica (e.g., KAl2(AlSi3O10)(OH)2 - muscovite or K(Mg,Fe)3AlSi3O10(OH)2 - biotite), among others.
Mineral, possibly rock fragment containing a mineral
Limestone (Weathered)
Sedimentary carbonate rock, primarily calcium carbonate (CaCO3)
sedimentary
Chert (Jasper)
Silicon Dioxide (SiO2)
sedimentary
Muscovite Mica
Muscovite (Potassium Aluminum Silicate Hydroxide Fluoride), KAl2(AlSi3O10)(OH,F)2
mineral
Shale
Argillite / Shale
sedimentary
Gold (Elemental Metal)
Gold (Au)
Mineral
Specular Hematite (Specularite)
Iron(III) oxide (Fe2O3)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Basalt
Basalt (Aphanitic Mafic Igneous Rock)
igneous
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Sandstone
Clastic Sedimentary Rock
sedimentary
Satin Spar Selenite
Gypsum (Calcium Sulfate Dihydrate, CaSO4·2H2O)
mineral
Silicon Carbide (Carborundum)
Silicon Carbide, SiC
mineral
Basalt (Vesicular/Waterworn)
Basalt (Mafic Extrusive Igneous Rock)
igneous
Biotite Mica
Biotite (K(Mg,Fe)3AlSi3O10(OH,F)2)
mineral
Petrified Wood
Silicified Wood (primarily Quartz or Chalcedony, SiO2)
mineral
Quartzite Pebble
Quartzite (mostly SiO2)
metamorphic
Red Jasper
Jasper (a cryptocrystalline variety of Quartz, SiO₂)
Sedimentary Rock
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Granite
Intrusive Igneous Rock
igneous
Conglomerate
Conglomerate (a clastic sedimentary rock)
Sedimentary Rock
Milky Quartz
Quartz (Silicon Dioxide, SiO2)
mineral
Banded Agate (with Quartz Geode Center)
Silicon Dioxide (SiO2)
mineral
Generic Pebble / Rock Fragment
Lithic fragment / Weathered rock
sedimentary
Conglomerate
Conglomerate (SiO2 matrix with varying clasts)
sedimentary
Sandstone
Sandstone (Siliciclastic Sedimentary Rock)
sedimentary
Granite
Phaneritic plutonic rock (Quartz, Feldspar, Mica)
igneous
Jasper
Microcrystalline Quartz (SiO2)
sedimentary
Unknown Organic Object (likely a berry or fruit)
Not applicable; this is not a geological specimen. If it were a cranberry, its scientific name would be Vaccinium macrocarpon; if a cherry, it would be Prunus avium or Prunus cerasus.
Organic Material (likely a fruit or berry)
Coquina / Shelly Sandstone
Calcareous Sandstone / Coquina
sedimentary
Chert Nodules (Limonitic Chert)
Cryptocrystalline Quartz (SiO2) with Hydrated Iron Oxides
sedimentary