How many gemstones start with C?

15 of the 170 gemstones in Icillion start with C, for example Citrine, Coral and Carnelian.

What is the longest name among gemstones that start with C?

The longest is “Conch pearl” and the shortest is “Coral”.

Science · lists

15 gemstones start with C, from “Cairngorm” to “Cuprite”. Every one of them counts as an answer in Icillion.

C is the 3rd most common first letter in this list: 15 of the 170 gemstones (9%).
Shortest: “Coral”. Longest: “Conch pearl”.
2 names have more than one word.
1 can be spelled more than one way, and all the spellings count.

How many gemstones start with C?: 15 of the 170 gemstones in Icillion start with C, for example Citrine, Coral and Carnelian.
What is the longest name among gemstones that start with C?: The longest is “Conch pearl” and the shortest is “Coral”.

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