Thanks to @History_of_Geology I know today is the birthday of Leopold von Buch, after whom the glassy rock "buchite" is named. 🎂

Mull is particularly famous for its aluminium-rich buchites, in which mullite was discovere + sapphires and other goodies. Here's a mullite buchite from an old #ThinSectionThursday - the long crystals are mullite, the clear background is glass, + together they are buchite. 🤩 More in alt txt.

FoV ca 1mm wide. #Geology #Microscopy #Mineralogy #IsleOfMull

Hard Carbonate of Lime (*Calx carbonata dura*) (1802–17) by James Sowerby, from British Mineralogy.

Source: Smithsonian Libraries and Archives / Biodiversity Heritage Library

https://pdimagearchive.org/images/ba1debec-9077-455b-a71c-0750e1d8736e

#minerals #marine #geology #biology #rocks #invertebrates #mineralogy #art #publicdomain

It may be Friday, but it's never too late for #ThinSectionThursday 😁 🤡 Here's a rock (from @geologymull) newly photo'd yesterday: a lovely fresh olivine dolerite from the very-rarely-visited Stac Mhic Mhurchaidh, an uninhabited rock west of Iona. The violet colour of the clinopyroxene crystals "bespeaks titanium" as the early C20th geological survey reports elegantly used to say. 🤓 😊 Field of view about 3.5mm wide. More image info in Alt-txt.

#Geology #Mineralogy #Mull #Igneous #Microscopy