- Aphanites (adj. aphanitic; from Ancient Greek αφανης (aphanḗs) ‘invisible’) are igneous rocks that are so fine-grained that their component mineral crystals are not visible to the naked eye (in contrast to phanerites, in which the crystals are visible to the unaided eye). This geological texture results from rapid cooling in volcanic or hypabyssal (shallow subsurface) environments. As a rule, the texture of these rocks is not the same as that of volcanic glass (e.g., obsidian), with volcanic glass being non-crystalline (amorphous), and having a glass-like appearance.
- Nauru (Wikipedia)
Nauru (/nɑːˈuːruː/ nah-OO-roo or /ˈnaʊruː/ NOW-roo; Nauruan: Naoero), officially the Republic of Nauru (Nauruan: Repubrikin Naoero) and formerly known as Pleasant Island, is an island country and microstate in Micronesia, part of the Oceania region in the Central Pacific. Its nearest neighbour is Banaba of Kiribati about 300 km (190 mi) to the east.
- Mineral (Wikipedia)
In geology and mineralogy, a mineral or mineral species is, broadly speaking, a solid substance with a fairly well-defined chemical composition and a specific crystal structure that occurs naturally in pure form.