Gemstone Beach Gems Off to Germany

I mentioned towards the end of a previous post that I had met Maike and Martin, a young couple from Germany, on Gemstone Beach in March. I agreed to tumble-polish some stones for them. Today I finished the process, and Petra my wife will take the stones to Germany when she travels there in a couple of days. 

Altogether, Maike and Martin collected 83 stones on Gemstone Beach. The largest is  6 cms by 3 cms, the smallest being about half the size of my small finger-nail. All 83 fitted nicely into a 3lb tumbling barrel. I am very impressed with the resulting product, an excellent set of polished Gemstone Beach “gems”! Maike and Martin collected well.

The following are photos of the original stones, dry, then how they looked after their first tumble in 320 grit, and then how they looked after their final polish: 

The 83 stones as found on the beach.

After the first tumble in 320 grit.

After the final polish.

Firstly, the stones were tumbled in 320 grade silicon carbide for seven days, then tumbled in Sunlight soap for six hours. Secondly, they were in a five-micron tin oxide “pre-polish” tumble for five days, then tumbled in Sunlight soap for 16 hours. Thirdly, a one-micron tin-oxide “pro-polish” stage took eight days, followed by 27 hours in borax soap. The whole process took 22 days. This is probably the shortest time I have ever polished stones, but the outcome was very good. Initially the stones weighed 780 grams, finishing up at 689 grams, thus losing 10% of their mass, most of it in the 320 tumble stage. 

The following photographs provide comparisons of some of the polished stones with how they looked initially, when found on Gemstone Beach. To start off with, here are three of the larger ones:

Maybe a kind of argillite, a mudstone.

Banded rhyolite stone.

Further comparisons for larger stones:

As found on the beach.

Polished.

Different textures.

As found on the beach.

As found on the beach.

Polished.

Some of the medium-sized stones:

Two polished stones.

Before polishing.

Before polishing.

Before polishing.

Polished.

As found on the beach.

Polished.

Smaller stones:

White quartz stones as they were on the beach – practically polished already!

Some other small stones from the beach.

Some small green stones from the beach.

The polished stones.

One of the stones is a small jasper button:

Before polishing.

The polished jasper stone is at the right.

Finally, some of the smallest stones collected by Maike and Martin:

Before polishing.

After polishing.

When packaging the stones to send to Germany, to complete Maike and Martin’s set of outstanding Gemstone Beach stones, I added a hydrogrossular garnet and a stone with a fossil worm cast. These are iconic Gemstone Beach gems, with the hydrogrossular garnet especially sought after, and the fossil worm cast being reasonably distinctive to this coast. As they were absent from Maike and Martin’s haul, I took the liberty of adding them to the package heading overseas.

Author: tumblestoneblog

Retired Academic, male, living in the New Zealand countryside near Whanganui with his wife as well as Jasper the dog, Fluffy the cat, Dancer and Penny, the horses, and a shed half-full of stones. Email john.tumblestone@gmail.com. View all posts by tumblestoneblog