Amblygonite

Amblygonite (/æmˈblɪɡəˌnaɪt/) is a fluorophosphate mineral, (Li,Na)AlPO4(F,OH), composed of lithium, sodium, aluminium, phosphate, fluoride and hydroxide.

Amblygonite occurs with spodumene, apatite, lepidolite, tourmaline, and other lithium-bearing minerals in pegmatite veins.

[3] It has been discovered in considerable quantity at Pala in San Diego county, California; Caceres, Spain; and the Black Hills of South Dakota.

As a gemstone set into jewelry it is vulnerable to breakage and abrasion from general wear, as its hardness and toughness are poor.

Australia, France, Germany, Namibia, and Norway, and Spain have also produced gem quality amblygonite.

Amblygonite from Taquaral, Itinga , Minas Gerais , Brazil. Scale at bottom is one inch, with a vertical line at one cm.