Just two days after his 87th birthday, and after a brief illness, Capt. John Sinkankas, famed gemologist and author, passed away suddenly and quietly at his home in San Diego.

Born on May 15, 1915, Sinkankas was an expert in gemology, mineralogy, the lapidary arts, gemological and mineralogical literature, bookbinding, gem and mineral collecting, and gemological and mineralogical history, as well as an accomplished artist-what some would call a Renaissance man. He was considered the prime authority on the subject of gemology.

Sinkankas was born and raised in the city of Paterson, a northern New Jersey town not far from the better-known cities of Hackensack and Newark. By the age of 7, John had wandered through Paterson’s mineralogically important basalt trap rock New Street quarry, and noted later in life that the minerals found there were “irresistibly fascinating.” He soon discovered four other quarries in the neighboring towns of West Paterson, Great Notch, Haledon, and Prospect Park. The local abundance of collectable minerals led him to a lifelong interest in mineralogy, geology, and gemology.

Sinkankas graduated with a Bachelor of Science degree from New Jersey State Teachers College, now called William Paterson College. But since jobs were scarce in 1936, he joined the Navy. Sinkankas would eventually earn the title of Captain, after a 25-year-long stint as a Navy pilot and commander. In the early part of his naval career, then-Ensign Sinkankas married his college sweetheart, Marjorie Jane McMichael, on February 5, 1940, in Key West, Fla.-beginning what would eventually be called one of the most successful partnerships in the field of gems and minerals. Sinkankas retired from the Navy in 1961, and settled in San Diego.

Immediately after retirement, Sinkankas joined the staff of the Lapidary Journal. Between 1961 and 1963, John wrote 14 gem and gem cutting articles. He went on to write hundreds of papers in such hobby and professional journals as Gems & Gemology, Journal of Gemmology, Lapidary Journal, Gems and Minerals, Rock and Gem, Rocks and Minerals, Mineral Digest, Mineralogist, American Mineralogist, and Mineralogical Record.

John and Marjorie loved books. Together, they operated Peri Lithon Books, one of the country’s finest dealers in antiquarian books on the earth sciences. (The name Peri Lithon came from the adaptation of a Greek title, On Stones, authored by Theophrastus in 450 B.C., apparently the oldest existing treatise on minerals.)

In 1988, their personal collection of more than 13,000 books and manuscripts-more than 40 years in the making-was acquired by the Gemological Institute of America, and today forms the nucleus of the Richard T. Liddicoat Library. This collection is housed in the specially designed humidity- and temperature-controlled Cartier Rare Book Repository and Archives. The Sinkankas collection includes virtually every major work related to the study of gems and jewelry. For example, C. Plinius Secundus, aka “Pliny,” who died in the eruption of Mt. Vesuvius in 79 A.D., authored one of the earliest and most celebrated academic treatises of all time, Natural History. Included in the Sinkankas collection are 29 different editions of Pliny’s Natural History, ranging from a Latin incunabulum published in 1496 to a 12-volume set written in French.

Sinkankas not only collected books, but authored them as well-15 of them, to be precise, including Gem Cutting: A Lapidary’s Manual, 1955; Gemstones of North America, 3 Vols., 1959-1997; Gemstones and Minerals: How and Where to Find Them, 1961; Mineralogy for Amateurs, 1964; Van Nostrand’s Standard Catalog of Gems, 1968; Gemstones & Mineral Data Book, 1972; Emerald and Other Beryls, 1981; Gemology: An Annotated Bibliography, 2 Vols., 1993; and Humboldt’s Travels in Siberia: 1837-1842, 1994.

In addition to his writing, Sinkankas also was an artist, and used his watercolor illustrations for Gemstones of North America and Emerald and Other Beryls.

Sinkankas earned or was honored with numerous titles, including:1982 – Ph.D., Honoris Causia, William Paterson College; 1984-in recognition of his contributions to the field, a new phosphate mineral was named sinkankasite in his honor; 1985-honorary membership in the Rochester (NY) Academy of Sciences; and 1988-awarded the first individual Carnegie Mineralogical Award.

Sinkankas was a Fellow of the Mineralogical Society of America (since 1967); an honorary Fellow of the Gemmological Association All-Japan; and held memberships in the Mineralogical Association of Canada, the Rochester Academy of Sciences (honorary), the San Diego Mineral and Gem Society (honorary), the Cosmos Club, Washington, D.C., and The Mineralogical Society of Southern California (honorary). A Graduate Gemologist of the GIA, he was presented with that organization’s Distinguished Associate Award in 1982.

Two of Sinkankas’ most important gem carvings-a 7,000-ct. rock crystal quartz egg and the world’s largest faceted step-cut golden beryl weighing in at 2,054 cts.-can be seen in the Gem Hall of the Smithsonian’s Natural History Museum.

John is survived by his wife, Marjorie; their four children, John William, Seattle, Wash.; George Martin, Knoxville, Tenn.; Sharon Jane Tooley, San Diego; and Marjorie Ellen Coates, Atlanta, Ga.; and six grandchildren.

Special thanks to William Larson and Richard Hughes, Pala International, and to Ron Thacker of the Mineralogical Society of Southern California, for the information provided here.

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