Quartz (likely macrocrystalline variety)

Hardness: 7 on the Mohs scale. Color: Appears translucent to milky white/gray, which is common for Quartz. Luster: Vitreous (glassy) to greasy. Crystal Structure: Hexagonal (though often massive or granular). Cleavage: None (exhibits conchoidal fracture). Specific Gravity: 2.65.

Quartz forms under a wide range of geological conditions. It can crystallize from magma (igneous), precipitate from hydrothermal solutions (hydrothermal), or form through metamorphic processes. The rounded shape suggests fluvial (river) or glacial transport, indicating it was eroded from a larger rock mass and smoothed over time. Geological Age: Quartz minerals can form throughout Earth's history, from Precambrian to recent times, depending on the specific geological setting.

Industry: Used in glassmaking, abrasives, foundry sands, and as a component in electronic oscillators and filters (due to its piezoelectric properties). Construction: A primary component of concrete and mortar. Jewelry: Amethyst, citrine, rose quartz, and smoky quartz are popular gemstone varieties.

Quartz is one of the most common minerals on Earth, making up about 12% of the Earth's crust. It is a major component of many rocks, including granite, sandstone, and gneiss. Its piezoelectric properties make it valuable in electronics, and its durability contributes to its widespread use as an abrasive and in construction materials.

Field Identification: Distinguished by its relatively high hardness (scratches glass), lack of cleavage, conchoidal fracture, and glassy to greasy luster. Common Locations: Found globally in various geological settings, including igneous, metamorphic, and sedimentary rocks, as well as in riverbeds and beach sands as eroded pebbles. Tips for Collectors: Look for its distinctive fracture and hardness. Pure quartz is clear, but impurities can give it various colors. The specimen appears to be water-worn, indicating it was likely found in a river, stream, or beach.