set of various nepheline stones cutout on white

aegirine background collage collection cut cutout gem gemological gemology gemstone geological geology igneous ijolite isolated lujaurit lujaurite lujavrite macro magmatic mineral mineralogy natural nepheline nephelite out pebble piece plutonic polished raw rock rough sample sanidine set specimen spreustein spreusteine spreusteined stone syenite tumbled unpolished urtite various volcanic white