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Ralph D. Clark
(1937-    )

Ralph Dennis Clark, prominent Colorado thumbnail collector, was born in Denver on April 12, 1937, the son of Mary J. and John P. Clark, a farm equipment salesman. He grew up in the Denver suburb of Fort Lupton and has lived in the Denver area all his life, except during his Air Force basic training and one business-related, two-year stay in Dallas, Texas. At the University of Colorado he studied electrical engineering and business administration and at the Community College of Denver he studied and then taught (part-time) consumer electronics.

Ralph's career has included 17 successful years with J. C. Penney in positions of increasing responsibility in Product Service management, culminating as Regional Product Service Manager in Dallas, where he was responsible for planning, organizing, developing and implementing product services and meeting business objectives and goals for a nine-state region. When J. C. Penney decided to discontinue the Product Service branch of its operations in 1983, Ralph went on to similar success working for RCA as Manager of their consumer and commercial service operations branch in Denver, then for General Electric (which acquired RCA in 1986) as Regional Quality Assurance Manager for their Major Appliance Division. He retired from General Electric in 1989, but continued to work full-time for a commercial real estate management company primarily to generate extra income for building his mineral collection. He is now retired and spends most of his time on church activities and cultivating his mineralogical knowledge, friendships, and contacts while refining his connoisseurship so that he may keep shaping and re-shaping his mineral collection.

Ralph collects primarily thumbnails (specimens that would fit within a one-inch cube), and his constantly evolving collection is of amazingly high overall quality. Piece-for-piece it is clearly one of the finest such collections in the world.

Ralph and his wife JoAnn, were married in 1956 and have three children: sons Don and Todd and a daughter Lori. JoAnn is wholly supportive of Ralph's passion for minerals and is respectful of his concentrated pursuit of connoisseur thumbnails. His interest in minerals was triggered in 1969 when Todd came home from first grade one day, very excited about a "show and tell" about fossils that one of the other kids had presented in class. Ralph and JoAnn soon found themselves joining the Gates Rock and Mineral Club and haunting rock shops during family trips. Tumbling, cabochon-cutting, and other lapidary amusements eventually gave way to crystal pursuits when Manuel Ontiveros, an El Paso, Texas dealer in Mexican minerals, showed the Clarks his personal collection, the first serious one they had ever seen. Ontiveros pointed them toward the Tucson Show and was otherwise very encouraging, but strongly advised that they should acquire only high-quality specimens, and not go "vacuum-cleanering" around the shows, merely scooping up pretty rocks in quantity. Promptly disregarding that advice, the Clarks purchased a flat of 20 Mexican miniatures for $20 from Ontiveros himself. But they soon learned to do better.

In 1971 mineral dealer Richard Kosnar ("Mineral Classics") moved to the Denver area, and the Clarks, after seeing his ads in the Mineralogical Record, paid him a visit. Ralph and his son, Don, became friends with Kosnar. They accepted him as their mentor in mineral collecting, and learned much from him. Although Kosnar himself favored miniatures, Ralph and Don zeroed in on thumbnails and began to build a serious thumbnail collection. Todd lost interest in collecting around 1974, but Don and Ralph continued to build their first collection until they sold it in 1977, just as Don was entering college. Today Ralph admits that (like many of us who have ever sold our minerals) there is a handful of pieces from his older collection that he would love to have back again.

A hiatus set in after 1977, and Ralph ended up waiting until 1986 to begin collecting again, all on his own this time. The first-generation collection was fine enough to have won the AFMS National Award for thumbnail minerals in 1974 and 1977. The second-generation collection scored more major competitive-display awards: "Best of Species--Thumbnails" at the Denver Gem & Mineral Show in 1990 and 1993, The "Richard Pearl Trophy" at the Denver Gem & Mineral Show in 1992 and 1995, and the AFMS National Award for thumbnail minerals in 1993."Best Master Minerals" at the Tucson Gem & Mineral Show of 1991, “Best of Show, Master Minerals” and the “Walt Lidstrom Memorial Award” at the Tucson Gem & Mineral Show of 2006 and “Best of Theme: Australia, Toenail” at the Tucson Gem & Mineral show of 2007. Ralph has displayed at major shows, not always competitively, but always effectively.

What Ralph loves are mineral species that are essentially at their best in the thumbnail/toenail size range, and not known to improve in larger sizes, though he does make exceptions. And once in a while he can't resist buying very inexpensive and "ordinary" specimens. But the really distinctive and most impressive pieces in his collection are those which combine rarity of species, exceptional form and/or crystal size (for the species), absolute freedom from damage, and the most impeccable aesthetics.

Sharing is one of the joys of collecting, and Ralph is always an eager and complimentary audience when others want to show off their own minerals. Likewise he hospitably welcomes appreciative visitors to his own home, and is always up for a "show and tell," especially if the guest is a serious mineral collector.


MOORE, T. P. (2002) Collector profile: Ralph Clark. Mineralogical Record, 33 (2), 181-186.
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WILSON, Wendell E. (2019)
Mineralogical Record
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The Mineralogical Record - Ralph D. Clark
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