Weathered granite or granitic gneiss
Granite; chiefly quartz, feldspar, and mica (possibly gneissic if foliation is confirmed)
igneous
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Anthropogenic (Man Made Material)
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Green copper-mineral specimen, likely chrysocolla or copper-bearing serpentine
Tentatively chrysocolla (hydrated copper phyllosilicate, approximately (Cu,Al)2H2Si2O5(OH)4·nH2O); exact identification requires testing
mineral
Weathered quartz-rich metamorphic rock, possibly quartzite
Quartzite; predominantly quartz (SiO₂), with minor feldspar, mica, and iron-oxide staining
metamorphic
Water-worn basalt cobble
Basalt; chiefly plagioclase feldspar, pyroxene, and minor olivine/iron oxides
igneous
Weathered quartz-rich rock, likely quartzite
Quartzite; predominantly crystalline SiO₂, possibly iron-oxide stained
metamorphic
Weathered quartz-rich rock, possibly granite or quartzite
Indeterminate; likely quartz–feldspar aggregate, possibly granitic gneiss
igneous
Biotite-rich granite or granitic gneiss
Granite; quartz–feldspar–biotite assemblage
igneous
Weathered granite or granitic gneiss
Granite; primarily quartz, feldspar, and mica (possibly metamorphosed to gneiss)
igneous
Fossiliferous limestone
Bioclastic carbonate rock, primarily calcite (CaCO₃)
sedimentary
Rounded quartz-rich beach pebble
Likely milky quartz or quartzite (SiO₂)
mineral
Green aventurine cabochon (likely)
Quartzite/aventurine quartz, predominantly SiO₂ with possible fuchsite mica
gemstone
Turquoise
CuAl6(PO4)4(OH)8·4H2O
mineral
Diamond
Carbon (C)
gemstone
Polished orbicular jasper (likely ocean jasper)
Silicified microcrystalline quartz/chalcedony (SiO₂), with iron-oxide and other mineral inclusions
gemstone
Milky Quartz
Silicon Dioxide (SiO2)
mineral
Limestone
Calcium Carbonate (CaCO3)
sedimentary
Shale with Trace Fossils
Fissile mudrock (Shale)
sedimentary
Polished orange agate/jasper cabochon
Microcrystalline quartz (chalcedony), SiO₂, with iron-oxide coloration; exact variety uncertain
mineral
Orbicular jasper (likely ocean jasper)
Silica-rich microcrystalline quartz/chalcedony with feldspar and accessory minerals; composition varies
mineral
Rounded gray pebble
Indeterminate; likely a water-worn silicate or carbonate pebble
sedimentary
Tumbled pegmatitic granite
Granite, chiefly quartz–feldspar–mica; likely altered pegmatite
igneous
Tumbled sodalite (probable)
Sodalite, Na₈(Al₆Si₆O₂₄)Cl₂
mineral
Rose quartz
Quartz (silicon dioxide, SiO₂), pink variety
mineral
Iolite
Cordierite (Mg2Al3(AlSi5O18))
gemstone
Sandstone
Sedimentary Rock (Quartz arenite)
sedimentary
Sandstone
Quartzose Sandstone (Sedimentary Rock)
sedimentary
K-Feldspar (Potassium Feldspar)
Potassium Feldspar (Microcline or Orthoclase), KAlSi3O8
mineral
Septarian Nodule
Septarian Concretion (Calcite, Aragonite, Limestone)
sedimentary
Graphic Granite
Pegmatitic Granite
igneous
Sandstone
Sedimentary Rock (Quartz arenite/Arkose)
sedimentary
Sandstone
Sedimentary Rock (Quartz Sandstone)
sedimentary
Sandstone
Quartz Arenite / Clastic Sedimentary Rock
sedimentary
Sandstone
Sedimentary Rock (Quartz Arenite)
sedimentary
Quartzite Pebble
Metamorphic Quartzite (SiO2)
metamorphic
Sandstone
Quartz Arenite / Sedimentary Rock
sedimentary
Sandstone
Sedimentary Rock (Quartz arenite)
sedimentary
Dumortierite Quartz
Dumortierite in Quartz (Al6O3(BO3)(SiO4)3)
mineral
Yellow Jasper with Red Inclusion
Silicon Dioxide (SiO2) with Iron Oxides
sedimentary
Amazonite in Quartz
K(AlSi3O8) - Potassium Feldspar with Quartz (SiO2)
mineral
River Pebble (Greywacke / Basalt Pebble)
Indeterminate Rounded Pebble (composed of quartz, feldspar, or mafic minerals)
sedimentary
Red Tuff / Sandstone
Rhyolitic Tuff / Pyroclastic Volcanic Rock
igneous
Quartz Pebble
Silicon Dioxide (SiO2)
sedimentary