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Birthstones For OctoberPrecious Opal and Pink Tourmaline are both listed as birthstones for October. The Opal may be white, with a play of colors giving it the name of fire opal, or it may be black. The physical structure is somewhat uncertain. Nevada and Idaho are the principal American sources, while Australia leads the foreign sources. The Pink Tourmaline is usually a transparent gem stone with a variety of colors. Some opaque forms occur. Coarse granite rocks in San Diego County in California and Maine are the best sources. Its hardness is 7 to 7.5. It has an uneven to conchoidal fracture, and a poor cleavage. |
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Utah Nature Study Society NATURE NEWS/NOTES October 1967 |
Adapted for The INTERNET by Sandra Bray |