Gemstones Formed Directly from Molten Rock: The Ruby Deposits of Chanthaburi-Trat, Thailand

  • Peter C. Keller


Molten lava erupting from fissures or volcanoes on the earth’s surface may be a source for gemstones. These hot lavas may contain gems in one of three ways: (1) Gemstones such as moonstone may be an essential constituent of the lava and crystallize as such as the lava cools; (2) in the final stages of cooling; when much of the magma has solidified, minerals such as topaz may crystallize in lithophysal (gas) cavities formed in the cooling lava; and (3) the lava may simply act as the vehicle that transports materials that crystallized at great depth to the surface. Such is the case with many alkaliolivine basalts, which may bring peridot, zircon, sapphire, or ruby up from 100-km depths (Fig. 5-1).


Alkali Basalt Water Cannon Cooling Lava Geologic Reconnaissance Eluvial Deposit 
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  1. Aranyakanon, P., and P. Vichit. 1979. Gemstones in Thailand. Unpublished report for the Economic Geology Division of the Ministry of Industry of Thailand.Google Scholar
  2. Bauer, M., and L. J. Spencer. 1904. Precious Stones (trans. of 1896 German text). Charles Griffin & Co., London. 647 pages.Google Scholar
  3. Berrange, J. P., and E. A. Jobbins. 1976. The Geology, Gemmology, Mining Methods and Economic Potential of the Pailin Ruby and Sapphire Gem-field, Khmer Republic. Institute of Geological Sciences Report 35, London. 32 pages.Google Scholar
  4. Broomfield, C. S., and A. R. Shride. 1956. Mineral resources of the San Carlos Indian Reservation, Arizona. U.S. Geol. Surv. Bull. 1027-n: 613–691.Google Scholar
  5. Chang, F. 1969. A trip to Chanthaburi, Thailand. Lapidary Journal 23:1020–1024.Google Scholar
  6. Charaljavanaphet, J. 1951. Gem deposits at Bo Na-Wong, Tok-Phrom, Bo-Rai in Chanthaburi and Trat provinces. Geologic Reconnaissance of the Mineral Deposits of Thailand: Geological Survey Memoir 1:148–150.Google Scholar
  7. Clabaugh, S. E. 1952. Corundum Deposits of Montana. U.S. Geol. Surv. Bull. 983.Google Scholar
  8. Coldham, T. 1985. Sapphires from Australia. Gems & Gemology 21(3): 130–146.CrossRefGoogle Scholar
  9. Gübelin, E. 1940. Differences between Burmese and Siamese rubies. Gems & Gemology 3:69–72.Google Scholar
  10. Gübelin, E. 1971. New analytical results of the inclusions in Siam rubies. Journal of Australian Gemmology 12(7): 242–252.Google Scholar
  11. Holloway, J. R., and C. Cross. 1978. The San Carlos Alkaline Rock Association. Arizona Bur. Geol. Min. Tech. Spec. Pap. 2:171–173.Google Scholar
  12. Javanaphet, J. C. 1969. Geological Map of Thailand 1:1,000,000. Department of Mineral Resources, Bangkok.Google Scholar
  13. Jobbins, E. A., and J. P. Berrange. 1981. The Pailin ruby and sapphire gemfield, Cambodia. Journal of Gemology 17(8): 555–567.Google Scholar
  14. Keller, A., and P. Keller. 1986. The sapphires of Mingxi, Fujian Province, China. Gems and Gemology 22:41–45.CrossRefGoogle Scholar
  15. Keller, P. C. 1982. The Chanthaburi-Trat gem field, Thailand. Gems & Gemology 18(4).186–196.CrossRefGoogle Scholar
  16. Keller, P. C., J. I. Koivula, and G. Jara. 1985. Sapphire from the Mercaderes-Rio Mayo area, Cauca, Columbia. Gems & Gemology 21(1) 20–25.CrossRefGoogle Scholar
  17. Keller, P. C., and F. Wang. 1986. A survey of the gemstone resources of China. Gems & Gemology 22:3–13.CrossRefGoogle Scholar
  18. Koivula, J. 1981. San Carlos peridot. Gems & Gemology 17205-214.Google Scholar
  19. Lacombe, P. 1970. Le massif basaltique quaternaire a zircons-gemmes de Ratanakiri, Cambodge nordoriental. French Bur. Recherches Geol. et Minieres Bull. (ser. 2) 4(2) 29–53; (4)33-71.Google Scholar
  20. MacNevin, A. A. 1971. Sources of sapphires in the New England District, New South Wales. New South Wales Geol. Surv. Quart. Notes 3:1–5Google Scholar
  21. Moreau, M. 1976. Nong Bon ou le rubis de thailande. Revue de Gemmologie a.f.g. 47:10–12.Google Scholar
  22. Pavitt, J. A. L. 1973. Sapphire mining in Chanthaburi (Thailand). Journal of Gemmology 13:302–307.Google Scholar
  23. Shigley, J. E. and E. E. Foord. 1984. Gem-quality red beryl from the Wah Wah Mountains, Utah. Gems & Gemology 20(4) 208–221.CrossRefGoogle Scholar
  24. Stamm, D. 1981. A star is born: New facets of Thailand’s gem trade. New Look Investor 13(8): 8–20.Google Scholar
  25. Taylor, G. C., and S. Buravas. 1951. Gem deposits at Khao Ploi Waen and Bang Ka Cha, Chanthaburi Province. Geologic Reconnaissance of the mineral deposits of Thailand. Geological Survey Memoir 1:144–148.Google Scholar
  26. Thompson, D. 1983. Sapphires in New South Wales. Dept. of Mineral Resources, New South Wales, Sydney, Australia.Google Scholar
  27. Vichit, P., S. Vudhichativanich, and R. Hansawek. 1978. The distribution and some characteristics of corundum-bearing basalts in Thailand. Journal of the Geological Society of Thailand 3:M4-1-M4-38.Google Scholar
  28. Vuich, J., and R. Moore. 1977. Bureau studies olivine resources on San Carlos Apache Reservation. Arizona Bur. Mines Field Notes 7(2): 6–10.Google Scholar
  29. Webster, R. 1975. Gems: Their Sources, Descriptions and Identification. Butterworths, London. 938 page, Butterworths, LondonGoogle Scholar

Copyright information

© Van Nostrand Reinhold 1990

Authors and Affiliations

  • Peter C. Keller
    • 1
  1. 1.Natural History Museum of Los Angeles CountyUSA

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