Talk:Pebbles/@comment-26996586-20181226064202/@comment-26662021-20181226173031

mango-pango, most gems are minerals, not rocks. Minerals are a solid compound subastance, whereas a rock is a mixture of compouns substances (so a load of minerals madhed together). I say most gems are minerals because lapis actually a rock (it contains minerals such as pyriite and calcite and lazurite and others I cant remeber lol) but because its so pretty it's used as orniments and in jewelery, this making it a gem. You're right in highlighting that bismuth as well is an exception to the 'gems' rule of SU, but although it is not a gem - it is sill a mineral as it is made of just one substance. Again, you're right in identifying that pearl is also unusual as it is made through a biological process and this is not a mineral, but (like lapis) because of its frequent use in jewelery and stuff its considered an 'organic gemstone'. Other organic gemstones include jet, amber and ivory etc. I'm not sue if im helping or confusing you at this point so I'll stop haha lemme know if you need any more clarification :)