Limestone or Chert Fragment
Sedimentary Rock / Microcrystalline Quartz · Mineral Specimen
Crystal System
Trigonal (for calcite) or Hexagonal (for quartz)
Mineral Group
Carbonates or Silicates
Chemical Formula
CaCO3 or SiO2
Formation Process
Sedimentary accumulation of marine skeletal fragments or chemical precipitation
About This Crystal
An opaque, light gray to beige, weathered and water-worn rock fragment held in the palm of the hand. It has a dull to earthy luster with a slightly rough and pitted surface texture from natural weathering.
Physical Characteristics
Color ranges from off-white to gray-brown, streak is white, fracture is uneven to sub-conchoidal, specific gravity is approximately 2.6 to 2.7, tenacity is brittle.
Optical Properties
Opaque with no significant optical phenomena visible in this raw, weathered state.
Hardness & Durability
Origin Region
Worldwide, commonly found in sedimentary basins and riverbeds
Hardness & Durability
Mohs hardness ranges from 3 for limestone up to 7 if chert/quartz, moderate durability depending on mineral composition.
Care & Maintenance
Wash gently with warm soapy water and a soft brush; avoid harsh acids if composed primarily of calcium carbonate.
Rarity & Value
Extremely common worldwide, low monetary value as a standard geological specimen.
Special Characteristics
May effervesce (react with bubbling) in dilute hydrochloric acid if composed mainly of calcium carbonate.
Lore & History
Often used in traditional grounding practices and represents the enduring, stable energy of the earth element.