Echinosphäriten-Kalk (Echinosphaerites Limestone)
Image: Stadtmuseum Berlin (CC BY 3.0)
Mineral NameEchinosphäriten-Kalk (Echinosphaerites Limestone)
Chemical FormulaCaCO3
Mohs Hardness3
Crystal Systemtrigonal
Streak Colorwhite
Cleavageperfect rhombohedral (for calcite)
Fractureuneven
Specific Gravity2.65
Colorslight grey, off-white, pale yellow
Transparencyopaque
Type LocalityHohensaaten gravel pit, Baltic region
Mineral GroupCarbonate rock
Usesbuilding material, cement production, paleontological study, collector's specimen
Associated Mineralscalcite, fossils (Echinosphaerites)
Rarityuncommon
Description
A light grey to off-white sedimentary rock, characterized by numerous circular to ovoid fossil structures of Echinosphaerites, some appearing as radiating white crystals, others as hollow cavities.
Geological Context
This fossiliferous limestone formed from the accumulation of marine organisms, primarily Echinosphaerites (cystoids), in a shallow marine environment during the Ordovician period in the Baltic region.
