Lots of gemstone- & other mineralogical-type names are/have been used in English. Ruby, Jasper, Jade, Opal, Pearl, Amber, Emery, & Coral are all pretty recognizable, and several more have been in rarer use as well--Amethyst, Garnet, Celestine, Diamond, Emerald, Sapphire, Topaz, Hyacinth, Beryl.
And so, here are a few more gems & minerals that could be used as names, IMO.
- Agate (AG-at, English; ah-GAHT, French)
- Ametrine (AM-eh-treen)
- Barytes (bah-RYE-teez) [archaic]
- Cadmia (KAD-mee-ah) [archaic]
- Chalcedony (kal-SED-oh-nee)
- Citrine (SIT-reen, SIT-rin)
- Covelline (KOH-vel-leen)
- Euclase (YOO-clays)
- Galena (gah-LEE-nah, gah-LEH-nah)
- Jacinth (JAY-sinth, jah-SINTH)
- Olivine (OL-ih-veen)
- Peridot (PEHR-ih-doh, PEHR-ih-dot)
- Tourmaline (TOHR-mah-leen, TOOR-mah-leen)
Gemstones in other languages (asterisks indicate established names):
- Ágata (AH-gah-tah, Spanish, Portuguese, Galician)--"agate". Italian is Agata (ah-GAH-tah) [also a form of Agatha].
- Ametista (ah-meh-TEES-tah, Italian)--"amethyst". Spanish is Amatista.
- Azurita (ah-soo-REE-tah, Spanish)--"azurite"
- Berillo (beh-REEL-loh, Italian)--"beryl"
- Biyu (bee-yoo, Mandarin [碧玉])--"jasper" [lit. "blue jade"]
- Lazurit (lah-ZOO-reet, Russian [лазурит])--"lapis lazuli". Japanese is Ruri (roo-ree) [ 琉璃--lit. "sulfur(?) glass"]
- Maragda (mah-RAHG-dah, Catalan)--"emerald". Spanish & Portuguese is Esmeralda* (fem).
- Mercan* (mehr-JAHN, Turkish, feminine)--"coral"
- Meripihka (MEHR-ih-pihh-kah, [the H is not silent] Finnish)--"amber"
- Nilam* (NEE-lam, Hindi, unisex)--"sapphire". Portuguese is Safira.
- Olivina (oh-lee-VEE-nah, Italian)--"olivine, peridot"
- Rubin (roo-BEEN, Czech, Danish, Dutch, German....)--"ruby". Italian is Rubino* (masculine).
- Yeşim* (yeh-SHEEM, Turkish, feminine)--"jade". Italian is Giada* (JAH-dah, feminine); Russian is Nefrit (NEH-freet) [нефрит].