Mineraloid (Cryptocrystalline Quartz)

Quartzite pebble

Quartzite (SiO2)

Quartz Pebble

Silicon Dioxide (SiO2)

Carnelian

Carnelian (a variety of Chalcedony) - SiO2

Red Jasper

Jasper (Silicon Dioxide based crypto-crystalline Quartz with Iron inclusions)

Red Jasper

Silicon Dioxide (SiO2) with Hematite inclusions

Jade (likely Nephrite Jade based on appearance)

Nephrite (a variety of actinolite, Ca2(Mg,Fe)5Si8O22(OH)2)

Crushed Stone (Gravel/Aggregates)

Crushed rock aggregate (varied composition including Granite, Limestone, and Quartz)

Sandstone (Quartzose Sandstone)

Arenite (primarily SiO2 with minor Fe2O3)

Gneiss (specifically a granitic gneiss cobble)

Gneiss (high-grade regional metamorphic rock)

Prasiolite and Quartz Crystal Cluster

Quartz (SiO2); Prasiolite is a variety of Quartz

Quartz (Iron-stained)

Silicon Dioxide (SiO2)

Pegmatite (likely Granitic Pegmatite)

Pegmatite (a coarse-grained igneous rock, often with granitic composition)

Gneiss

Gneiss (a type of metamorphic rock)

Banded River Rock / Gneiss (highly weathered)

Gneiss

Snowflake Obsidian

Volcanic Glass with Cristobalite inclusions

Rose Quartz

Silicon Dioxide (SiO2) with trace amounts of titanium, iron, or manganese

Greisen

Greisen

Sandstone

Quartz Arenite (a common type of sandstone, given the appearance), Arkose, Greywacke (depending on mineralogy)