metamorphic
Tumbled blue-gray stone, likely quartzite or chalcedony
Quartz-rich rock; predominantly microcrystalline or granular SiO₂, identification uncertain from image
AI-generated identification · may be incorrectHardness approximately 6.5–7 Mohs; smooth rounded surface, blue-gray and tan-brown mottling, waxy to dull luster, no visible cleavage, and likely compact quartz structure. The brown area may be iron-oxide staining or weathered matrix.
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Physical properties
Hardness approximately 6.5–7 Mohs; smooth rounded surface, blue-gray and tan-brown mottling, waxy to dull luster, no visible cleavage, and likely compact quartz structure. The brown area may be iron-oxide staining or weathered matrix.
Formation & geological history
Likely a naturally quartz-rich pebble formed by sedimentary deposition and/or metamorphism, then rounded by water or mechanical tumbling; its geological age and exact locality cannot be determined visually.
Uses & applications
Suitable as a decorative tumbled stone, craft material, or paperweight; generally little industrial or jewelry value unless it proves to be a notable variety such as blue chalcedony.
Geological facts
The image cannot reliably distinguish quartzite from chalcedony, jasper, or another dyed/coated tumbled stone. A scratch test and examination of an unpolished area would substantially improve identification.
Field identification & locations
Commonly found in stream gravels, glacial deposits, and lapidary collections. Test whether it scratches glass and inspect translucency, banding, dye concentration, and bubbles; bubbles would suggest glass rather than stone.
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