Semi-precious sand

Olivine grains from the green beach on Big Island of Hawaii. With a magnitying glass each one is quite regular and glassy, but as the olivine was formed by crystallization in the molten lava it is normally only in small grains and large bits are rare. The governor collects rocks from everywhere we go, we had to buy a lucky Tikki in Hawaii to offset the bad luck caused by exporting a bit of Mauna Kea the big active volcano.
A propos of nothing this but I need to Blip early 'cos we're off to collect the governor's Mum today from Portsmouth.