Gem species known for this phenomenon include the aforementioned quartz, chrysoberyl, beryl ( especially var . moonstone, thomsonite and scapolite amongst others.
12.
These thomsonite nodules have concentric rings in combinations of colors : black, white, orange, pink, purple, red, and many shades of green.
13.
It occurs in serpentine altered dolostone in association with skarn enriched in tungsten, strontium, beryllium and boron in the Keralia occurrence and in vugs with natrolite and thomsonite in Norway.
14.
Prior to 1997, thomsonite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series name, with the mineral species being named thomsonite-Ca and thomsonite-Sr . Thomsonite-Ca, by far the more common of the two is a hydrous sodium, calcium and aluminium silicate, NaCa 2 Al 5 Si 5 O 20 ?H 2 O . Strontium can substitute for the calcium and the appropriate species name depends on the dominant element.
15.
Prior to 1997, thomsonite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series name, with the mineral species being named thomsonite-Ca and thomsonite-Sr . Thomsonite-Ca, by far the more common of the two is a hydrous sodium, calcium and aluminium silicate, NaCa 2 Al 5 Si 5 O 20 ?H 2 O . Strontium can substitute for the calcium and the appropriate species name depends on the dominant element.
16.
Prior to 1997, thomsonite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series name, with the mineral species being named thomsonite-Ca and thomsonite-Sr . Thomsonite-Ca, by far the more common of the two is a hydrous sodium, calcium and aluminium silicate, NaCa 2 Al 5 Si 5 O 20 ?H 2 O . Strontium can substitute for the calcium and the appropriate species name depends on the dominant element.
17.
Prior to 1997, thomsonite was recognized as a mineral species, but a reclassification in 1997 by the International Mineralogical Association changed it to a series name, with the mineral species being named thomsonite-Ca and thomsonite-Sr . Thomsonite-Ca, by far the more common of the two is a hydrous sodium, calcium and aluminium silicate, NaCa 2 Al 5 Si 5 O 20 ?H 2 O . Strontium can substitute for the calcium and the appropriate species name depends on the dominant element.
