Countertop geology: Orbicular granite, Boogardie Station, Mt Magnet, Western Australia

 

Orbicular granite featuring a large vein which has bisected a number of the orbs. The vein in the upper right seems to have experienced a significant level of movement resulting in the offset of a previous creamy coloured up/down vein.

 

A closer look at the orbs and their growth patterns. SHRIMP U-Pb analysis of the matrix titanite is 2687 ± 5 Ma (one of the oldest known orbicular granites)

A brief outline of the Boogardie Granite for the National Rock Garden and the mindat entry.

Photos were taken in the Melbourne Museum on the  May 7th, 2015 (yes, I know, this post took a while. There's a good reason for that!).