Leonard James Spencer CBE FRS[1] (7 July 1870 – 14 April 1959) was a British geologist. He was an Honorary member of the Royal Geological Society of Cornwall, and also a recipient of its Bolitho Medal.[2][3] He was president of the Mineralogical Society of Great Britain and Ireland from 1936 to 1939.[4] In mineralogy, Spencer was an original investigator who described several new minerals, including miersite, tarbuttite and parahopeite. He also did important work as a curator, editor and bibliographer.[5] He was the third person to receive the Roebling Medal, the highest award of the Mineralogical Society of America.[6] In 1937, he was awarded the Murchison Medal of the Geological Society of London. He wrote at least 146 articles for the Encyclopædia Britannica Eleventh Edition.[7]
His daughter, Penelope Spencer became a successful free-style dancer and choreographer.[8]