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The large deposit of distinctive orange to red "fire" opals at Querétaro, Mexico, is believed to be unique. To help solve the mystery of this unusual occurrence, modern techniques were used by authors R.J. Spencer, A.A. Levinson, and J.I. Koivula to determine the composition of the original liquid from which the gems formed. The stones shown here illustrate the variety of fine opals recovered from Querétaro. Fabricated in the early 20th century and signed by Theodore B. Starr, the Celtic buckle is composed of yellow gold, emeralds, sapphires, and diamonds, in addition to opal. The buckle is courtesy of R. Esmerian, Inc., New York. The 80.12-ct rough opal and the 16.27-ct cabochon are courtesy of Pala International, Fallbrook, CA. Photo © Harold & Erica Van Pelt—Photographers, Los Angeles, CA. |
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