an uncommon mineral, calcium borosilicate, CaBSiO4(OH), that occurs as white or colourless veins and cavity linings in basic igneous rocks and in metallic-ore veins. Some notable deposits exist in the United States: Westfield, Mass.; Bergen Hill, N.J.; and the Lake Superior copper district. Others have been found in Norway, various places in Italy, and Tasmania. For detailed physical properties, see silicate mineral (table)
Learn more about datolite with a free trial on Britannica.com.