Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Extrusive volcanic rock)
Category
Browse sedimentary or igneous specimens identified by the Rock Identifier community.
Amygdaloidal Basalt
Amygdaloidal Basalt (Mafic Extrusive volcanic rock)
Diabase (Dolerite) Cobble
Diabase / Dolerite
Apache Tear
Hydrated Obsidians (Volcanic Glass)
Basalt
Basalt (composition predominately Plagioclase feldspar and Pyroxene)
Basalt (River Pebble)
Basalt (extrusive mafic rock)
Granite
Granite (Felsic Plutonic Rock)
Basalt with Epidote (Greenstone)
Amygdaloidal Basalt (Ca2(Al, Fe)3(SiO4)3(OH) inclusions)
Granite
Granite
Granite (weathered cobble)
Granite
Pumice
Pumice (Vesicular volcanic glass / Rhyolite or Trachyte)
Apache Tear (Obsidian)
Volcanic glass (SiO2 - Silicon Dioxide)
Basalt Porphyry (River Pebble)
Porphyritic Basalt
Vesicular Basalt
Basalt
Scoria (Lava Rock)
Vesicular Basalt / Scoria
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Obsidian
Volcanic glass (high silica content based on SiO2)
Pumice
Pumice (volcanic glass formed of highly vesicular rough textured rock)
Obsidian
Volcanic Glass (SiO2)
Granodiorite with Biotite Mica
Granodiorite (containing Quartz, Plagioclase Feldspar, and Biotite Mica)
Red Jasper (Amygdaloidal Basalt with Agate)
Silicon dioxide (SiO2) in Basalt host
Basalt
Mafic volcanic rock (formula varies by mineral content: Ca-plagioclase, Pyroxene, Olivine)
Granitic Gravel Piece
Granite (Felsic Plutonic Rock / SiO2 with Al2O3, K2O, Na2O)
Basalt with Epidote/Chlorite
Amygdaloidal Basalt (SiO2 with (Ca2(Al2,Fe)(SiO4)(Si2O7)O(OH)))
Obsidian
Obsidian (Volcanic Glass, SiO2 + impurity isotopes)
Granitic Pegmatite
Granite Pegmatite (principally KAlSi3O8, SiO2, and KAl2(AlSi3O10)(OH)2)
Granite
Granite (Felsic Plutonic Rock)
Andesite
Andesite (intermediate volcanic rock)
Granite
Phaneritic Plutonic Felsic Rock
Granite
Granite (Felsic Plutonic Rock)
Vesicular Basalt (or Scoria)
Vesicular Basalt (Aphanitic-vesicular volcanic rock)
Basalt (River Pebble)
Basalt (Aphanitic Mafic Volcanic Rock)
Kimberlite
Kimberlite (Potassic ultramafic volcanic rock)
Sodalite Syenite (popularly known as Yooperlite)
Sodalite-rich Syenite (composed of alkali feldspar and sodalite)
Basalt
Mafic volcanic rock (Basalt)
Apache Tears (Obsidian)
Hydrated Volcanic Glass (Amorphous SiO2 + H2O)
Amygdaloidal Basalt
Basalt with secondary mineral infilling
Porphyritic Basalt (Chinese Writing Stone)
Porphyritic Basalt or Porphyritic Andesite
Rhyolite
Rhyolite
Basalt
Basalt
Basalt River Stone
Basalt
Basalt
Mafic Volcanic Rock (composed of Plagioclase Feldspar and Pyroxene)
Pumice
Pumice (a highly vesicular amorphous volcanic glass)