Grattarolaite is a rare mineral that belongs to the zeolite group. It is named after the type locality where it was first discovered in the Grattarola mine, Massa, Italy. This mineral is not widely known and has limited occurrence worldwide.
Grattarolaite typically occurs as small crystals in vugs or cavities in vesicular basalts, originating from volcanic activity. It is often found in association with other zeolite minerals such as phillipsite, chabazite, and laumontite. It has a white to colorless appearance and is translucent in nature.
In terms of physical properties, grattarolaite is relatively soft with a Mohs hardness of around 3. It has a monoclinic crystal system and a prismatic crystal habit, often forming acicular or fibrous aggregates. The mineral has a vitreous to pearly luster and a perfect cleavage in one direction.
Chemically, grattarolaite is a hydrated aluminosilicate, with its chemical formula usually represented as (Ca,Na2,K2)2[Al4Si14O36]·14H2O. It contains calcium, sodium, potassium, aluminum, silicon, and water as essential components. The water content gives grattarolaite its characteristic hydrous nature and contributes to its zeolitic properties.
Despite its rarity and limited commercial uses, grattarolaite is of interest to scientists and collectors due to its unique crystal structure and association with other zeolites. Its presence in volcanic rocks provides insights into the geological processes that occurred during their formation.
