What are some eight-letter gemstones?

21 of the 170 gemstones in Icillion have exactly 8 letters, for example Sapphire, Amethyst and Obsidian.

Which eight-letter gemstones start with S?

S is the most common first letter here, with 5 names, such as Sapphire, Sardonyx, Sodalite, Sugilite and Sunstone.

Science · lists

21 eight-letter gemstones in alphabetical order, from “Amethyst” to “Sunstone”. Each one counts as an answer in Icillion.

21 of the 170 gemstones have exactly 8 letters (12%).
Most start with S (5), A (4) and H (3).
Only names of one word are counted, and only their letters: spaces, hyphens and apostrophes are not.

What are some eight-letter gemstones?: 21 of the 170 gemstones in Icillion have exactly 8 letters, for example Sapphire, Amethyst and Obsidian.
Which eight-letter gemstones start with S?: S is the most common first letter here, with 5 names, such as Sapphire, Sardonyx, Sodalite, Sugilite and Sunstone.

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