Tom is the staff mineralogist for The Arkenstone and is an independent exploration consultant for the gold mining industry. He has a passion for and research interest in granite pegmatites and specializes in their geology and mineralogy. Much of his mineral collection is devoted to common and rare mineral species originating from lithium-cesium-tantalum type granite pegmatites. Tom has spent considerable time studying and appreciating the mineralogy of Brazilian pegmatites as well as those from his home state of South Dakota. During his research on granite pegmatites he discovered three new minerals: tiptopite, fransoletite, and pahasapaite and co-described eight other species new to science. Tom is also a co-author of the second edition of the Encyclopedia of Minerals with Bill Roberts and George Rapp, Jr and has published numerous papers in professional journals.
Gem Crystal Pegmatite Pocket Formation and Survival
Mineral specimens from gem-bearing pegmatites represent some of the most profound display pieces in both private and public collections with the finest pieces constituting natural art and investments. What some collectors and the general public may not appreciate is how uncommon single gem crystals and combination specimens containing tourmaline, aquamarine, morganite, topaz and yes, rare species such as amblygonite, herderite, beryllonite, petalite and others actually are! When we see them on display we tend to take their beauty for granted and sometimes forget about the complex journey they have made to make it to their final destination. This journey includes the complexity of their evolution from granite melts, miarolitic cavity (pocket) formation, the process of gem crystal growth, not to mention their survival in the Earth’s crust for many millions to sometimes over a billion years! And then there is the excitement of discovery and the fastidious extraction process which makes us appreciate how wondrous these gem crystals truly are!