Updated: Sep 30, 2020
Based on 'Rock glazes of NZ'
Sample 90. Sand near Omarama
Considerable quartz, rather weathered feldspar, sericite, occasional small grains of clinozoisite sphene and rarely zircon. Almost certainly derived from schist
When researching sand near Omarama the 'Clay cliffs' comes up in many searches. Considering they formed in the past 2 million years they were defiantly part of the landscape of the 1950s but whether they were accessible then I'm unsure. The cliffs are on private land and way too amazing for me to even consider sampling for glaze material. I took nothing but photos.
I have included these photos though as Sample 90 is labelled 'sand near Omarama'. River sand is usually stated as river sand and this sample doesn't name a river. Perhaps Bondy choose her sample from the clay cliffs based on the geological composition?
Kate Pedley's entry on the Geotrips website has great information on the geology, and the pale grey sandstone that is present on the paths and in the car park may have been the original sample, although the description sounds more like actual sand, it may have been the more yellow alluvial clays.
For this sample, I instead headed to the nearest river The Ahuriri. Technically It's still 'Sand near Omarama' but may vary in its composition to the original sample by a few million years!
Geology is pretty crazy like this, especially in the South where fault lines have pushed up the land and within a small geographic area, you have a completely different rock.
Test A13, B13