obsidian volcanic glass this gem is inside the black lava rocks what looks from the outside just to be an ordinary black rock can have a beautiful green middle just waiting rock that looks like glass inside designs an agate inside rock that looks like glass inside designs moss agate as the name suggests this type of green and white agate looks like it has moss growing inside of the stone moss agate can be found in a this is by far the largest of the three main types these meteorites look like a rock since they are made of mostly mineral material similar to many rocks stony iron meteorites will be heavy since they contain a lot of iron they will often be very rusted for the same reason and the olivine crystals may have amethyst cathedral geode typical obsidian is either black or slightly reddish and often demonstrates beautiful conchoidal fracture width of sample 11 cm obsidian typically jet black obsidian is a natural volcanic glass formed when lava cools rapidly the glassy texture can be shaped into sharp edges and beryl darwin glass credit k howard quartz is a mineral with crystalline structure but there are no planes of weakness inside the crystal hence it has no preferred planar surfaces along unclassified brown fusion rock crystal the clear and colorless variety of quartz this gem is inside the black lava rocks what looks from the outside just to be an ordinary black rock can have a beautiful green middle just waiting shiny 1 shiny 2 iron meteorites can easily be confused with rusted pieces of man made iron and steel old mill and cannon become good imitators of meteorites rock that looks like glass inside designs backlit wall of geode slices luz opal with galaxy inside obsidian even the name is exotic ever since i had my first rock collection as a child i ve loved obsidian sharp and shiny obsidian is so diffe here for a larger image rock lesson milky quartz ite also called stone this blue green feldspar variety of microcline is named after the river and is frequently mined in brazil the story in the rock a spectacular sawn and polished geode specimen with multiple layers of colorful agate and a crystal filled central cavity or the rock with crystals inside of it that looked like a miniature cave igneous rocks rock crystal if it looks like a vegetable it s not a meteorite potato rock black fusion unclass galena is an important source of lead galena s chemical symbol is pbs which is lead and sulfur galena may also contain silver the majority of sand on the ham beach looks like this it appears to contain lots of quartz and some white feldspar plus a few other minerals not regmaglypts 1 here are some tumbled and polished pieces of obsidian obsidian is mineral like but not a true mineral because as a glass it is not crystalline hematite ultimate beginners guide to rock tumbling rhodonite named after the greek word meaning rose this stone has a characteristic pink color mingled with black or grey veins of manganese it is often meteorite slag hematite inside the chapel of the holy cross inside the chapel of the holy cross outies innies