mineral

Tumbled quartz-rich rock, possibly calcite or sandstone

Indeterminate from photograph; likely microcrystalline quartz (SiO₂) or calcite (CaCO₃)

AI-generated identification · may be incorrect

Cream-tan, opaque, rough-to-matte surface with no visible crystals; hardness is uncertain—quartz is Mohs 7, calcite 3, and sandstone typically 2–7 depending on cement. The rounded shape suggests natural abrasion or human tumbling.

Identified September 7, 2026More mineral →

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At a glance

Common name: Tumbled quartz-rich rock, possibly calcite or sandstone
Scientific name: Indeterminate from photograph; likely microcrystalline quartz (SiO₂) or calcite (CaCO₃)
Category: mineral
Identified: September 7, 2026
Method: Standard

AI Estimated Value

About $0–$5 as an unidentified common fragment; potentially $5–$25 if confirmed as an attractive collectible mineral.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Could be a weathered fragment of quartzite/sandstone or a calcite-rich mineral specimen; exact formation and geological age cannot be determined visually. Such materials form in sedimentary or metamorphic environments over millions of years.

Uses & applications

Common pieces may be used as curios, lapidary material, or aggregate; it has little jewelry or commercial value unless testing reveals an attractive mineral or fossil.

Geological facts

A steel knife or copper coin can help distinguish possibilities: calcite scratches easily, while quartz does not. Dilute vinegar may fizz on calcite but not quartz, though testing should be done cautiously.

Field identification & locations

Inspect for grains, layering, cleavage, and acid reaction; a glass-scratch test and streak test are useful. Similar pale specimens occur worldwide, especially in sedimentary terrains.