Gem-quality pink fluorite from Planggenstock, Switzerland: chemical and physical properties and a comparison with pink fluorites from other localities

Larimar, a massive blue variety of the mineral pectolite, belonging to the wollastonite group of min

Most of the spinels are found in shades of red to purple. Colourless, green and cobalt bearing varie

Corundum, encompassing the highly prized ruby and sapphire varieties, stands as a cornerstone of the