Flint
Quartz var. Flint · Mineral Specimen and Historical Tool Material
Crystal System
Trigonal, microcrystalline cryptocrystalline quartz habit forming massive or nodular masses
Mineral Group
Silicates, specifically tectosilicates
Chemical Formula
SiO2
Formation Process
Sedimentary, formed by the replacement of calcium carbonate by silica-rich solutions in marine environments diagenesis
About This Crystal
A small, water-worn, tumbled nodular pebble with a dark greyish-blue color, opaque transparency, and a dull to sub-vitreous luster showing minor surface weathering and scratches from transport
Physical Characteristics
Dark grey to black body color, white streak, no cleavage, distinctly conchoidal fracture, specific gravity around 2.60 to 2.65, brittle tenacity, hardness makes it scratch glass easily
Optical Properties
Microcrystalline aggregate displaying aggregate birefringence under polarized light, singly or complexly intersecting microscopic quartz crystals, entirely non-pleochroic
Hardness & Durability
Origin Region
Worldwide, commonly found in chalk and limestone formations globally, notably in Western Europe, the United States, and the UK
Hardness & Durability
Mohs hardness of 7, excellent toughness due to its microcrystalline interlocking structure, highly stable chemically, extremely durable for wear and historical tool usage
Care & Maintenance
Washable with warm soapy water, highly resistant to household chemicals, stable in sunlight, and requires no special storage precautions due to high durability
Rarity & Value
Extremely common worldwide, low monetary value as a mineral specimen unless shaped as ancient artifacts, widely used historically for fire-starting and weaponry
Special Characteristics
Exhibits exceptional conchoidal fracture allowing sharp edges when struck, historically used for creating sparks with steel for fire-making and knapping into stone tools
Lore & History
Deeply significant in human history as one of the primary materials for Paleolithic and Neolithic stone tools, arrowheads, and fire-starting kits; in modern crystal lore associated with grounding, cutting through negative energy, and protection