Gold Sheen Obsidian
Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)
Category
Browse non geological specimens identified by the Rock Identifier community.
Gold Sheen Obsidian
Volcanic Glass (SiO2 + Fe3O4 / Gas Inclusions)
Obsidian
Obsidian (Volcanic Glass)
Man-made Synthetic Material (Plastic/Composite)
Acrylonitrile Butadiene Styrene (ABS) or High-Impact Polystyrene (HIPS)
Quartzite
Quartzite (primarily SiO2)
Obsidian
Obsidian (principally SiO2)
Obsidian
Obsidian (principally SiO2 - Silicon Dioxide)
Obsidian
Volcanic Glass (SiO2, usually >70% silica content)
Obsidian
Obsidian (Volcanic Glass, primarily SiO2)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Slag Glass (Cullet)
Amorphous Silica / Glass residue
Obsidian
Volcanic Glass (predominantly SiO2)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Obsidian
Volcanic glass (SiO2 - Silicon Dioxide)
Gold Nugget
Native Gold (Au)
Obsidian
Volcanic glass (no mineral formula due to amorphous structure, mostly SiO2)
Sandstone
Sandstone (clastic sedimentary rock, composed predominantly of sand-sized minerals or rock fragments)
Quartzite
Metamorphosed Quartz Sandstone (SiO2)
Obsidian
Volcanic Glass (predominantly SiO2, approximately 70% or more)
Mahogany Obsidian
Obsidian (Volcanic Glass) with Hematite/Magnetite inclusions
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (70% or more silicon dioxide)
Obsidian
Obsidian (volcanic glass), primarily SiO2 (silicon dioxide)
Opalite (a synthetic glass)
Silicon Dioxide (SiO2) with various additives; not a true mineral but a man-made gem simulant
Apache Tear
Obsidian (Hydrated Volcanic Glass - SiO2)
Obsidian
Volcanic Glass (Primary composition: SiO2 - Silicon Dioxide)
Obsidian
Obsidian (principally SiO2)
Obsidian
Volcanic glass (high silica content, usually >70% SiO2)
Baroque Pearl
Biogenic Calcium Carbonate (Aragonite/Conchiolin)
Quartz (likely) or a Quartzite Pebble
Silicon dioxide (SiO2) for quartz. If it's quartzite, it's a metamorphic rock primarily composed of quartz.
Mahogany Obsidian
Obsidian (Volcanic Glass) with Hematite or Magnetite inclusions, SiO2 (Silicon Dioxide)
Milky Quartz
Silicon Dioxide (SiO2)
Horse Chestnut (Buckeye seed)
Aesculus hippocastanum seed
Tumbled Obsidian (possibly Mahogany Obsidian variant)
Volcanic Glass (Amorphous Silicon Dioxide, SiO2)
Obsidian
Obsidian (Volcanic Glass), primarily SiO2 (Silicon Dioxide)
Black Obsidian
Volcanic Glass (predominantly SiO2, Silicon Dioxide)
Magnetic Hematite
Magnetized Hematite (an iron oxide mineral, Fe2O3, that has undergone magnetization)
Obsidian
Volcanic glass (Mainly SiO2)
Snowflake Obsidian
Volcanic glass with Cristobalite inclusions (mostly SiO2)
Mahogany Obsidian
Volcanic Glass with Hematite/Magnetite inclusions (SiO2 + Fe2O3)
Moonstone with Black Tourmaline
Orthoclase (KAlSi3O8) with Schorl inclusions (NaFe3Al6(BO3)3Si6O18(OH)4)
Obsidian
Volcanic Glass (70-75% SiO2 with MgO and Fe3O4)
Rose Quartz
Rose Quartz (SiO2)
Anthracite Coal
Anthracite (a variety of coal, predominantly carbon)