Non-fossil Mineral Specimen (Quartz Crystal)
Quartz (var. Rock Crystal) • None (Geological Mineral Specimen)
Geological Period
Indeterminate (Likely Proterozoic to Cenozoic depending on locality)
Estimated Age
Not applicable (Geological mineral formation)
Preservation Type
Abiotic Crystallization
Condition Assessment
Good (as a mineral specimen); exhibits some contact damage, internal twinning, and iron staining on one facet.
Taxonomic Classification
Kingdom: Mineral; Class: Silicate; Species: Quartz (SiO2)
Morphological Description
A crystalline mineral aggregate showing trigonal symmetry, hexagonal prism faces (m), and rhombohedral terminations (r and z). It displays vitreous luster, conchoidal fracture, and lack of biological symmetry or organic structures (pores, septa, or vascularity).
Rock Matrix
None attached; however, small brownish inclusions suggest an iron-oxide or clay-based host matrix.
Formation & Location
Commonly found in hydrothermal veins, pegmatites, and geodes globally; notable deposits include Arkansas (USA), Brazil, and the Alps.
Size & Dimensions
Approximately 3-5 cm in length based on scale relative to marble texture; typical for small crystal clusters.
Value & Rarity
Estimated Market Value
$5.00 - $15.00 USD
Auction Estimate
$10.00 - $20.00 USD
Rarity Assessment
Common (Quartz is the second most abundant mineral in Earth's continental crust).
Scientific Significance
Low paleontological significance; high geological significance for studying hydrothermal fluid compositions and crystal growth kinetics.
Preparation Recommendations
Cleaning with water and mild detergent; ultrasonic cleaning if no fragile inclusions are present; display in an acrylic base or specimen box.
Notable Features
Doubly terminated appearance or intergrown cluster with significant iron-oxide (limonite/hematite) staining on the surface of one crystal face.