Rhyolite – Page 2 – TumbleStone

To mark Day Three of this second National Lockdown in New Zealand, this is a small polished rhyolite stone from Slope Point.

Side 1 of small rhyolite stone from Slope Point.

Side 2 of small rhyolite stone.

View of the top of the stone.

Slope Point is the southernmost bit of land of the South Island, New Zealand, 70 kilometres east of Invercargill. Tourists are directed to a carpark and walk across a large paddock to a well-known sign high atop cliffs. The sea and wind can be especially ferocious there.

The southernmost point of the South Island.

The sign that Tourists like to photograph. No access to beaches at this point.

Slope Point is an area known for rhyolites and petrified wood, and other volcanic pebbles and petrified material. Rhyolite is a volcanic rock with a high silica content (obsidian, pumice and ignimbrite are common varieties of rhyolite). Rhyolite stones can be colourful, with intricate patterns, and they often polish well. Access to a beach in the Slope Point area is not straightforward – there are many high cliffs and no road goes close to any of the small beaches. Earlier this year I made contact with a local resident and rockhound, Oliver Simpson, through the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils”. In March, he showed me how to get to a beach there and we spent some time fossicking for stones. I made two other visits there with Oliver in June.

The Slope Point beach where the stone was found.

Oliver on the beach.

This stone was among the first batch of Slope Point stones that I polished, completed only recently, with another couple of batches due to finish over the next couple of weeks.

See here for an earlier Post introducing Slope Point and its stones.

Stone of the Day #4 is here.

This is the sixth in this Series reproducing my recent regular Posts in the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils”. The first Post in this Series is here.

Tuesday 18 May 2021: Another recently tumble-polished small beach agate (chalcedony) from Birdlings Flat. Not banded this time. I decided to try to retain some of its outer character so did not wear away all of the brown and white material in the tumbler – and the result is very interesting. The stone is 3.5 cms long, having some small indentations but otherwise smooth.

One side of the polished stone.

Other side of the polished stone.

Held up to a sunny sky.

Wednesday 21 May 2021: This is the day I made a Post in the Group’s Alphabetical Series – “C” is for “Coral” – see this Post.

Thursday 20 May 2021: A small tumble-polished rhyolite from Slope Point (southern-most point of the South Island). Collected there on 3 March during a visit with Oliver Simpson [see previous Post]. Its wavy lines caught my eye on the beach.

It is a small stone.

One side of the polished stone.

Treasure

Another side of the polished stone, with a rough area apparent.

The beach near Slope Point on which the stone was found. To the right is the edge of a lagoon, with the open sea to the left (and ahead).

Oliver Simpson on the beach – many thanks to him for the day’s outing.

It has come out of a 3lb barrel this morning, my first completed batch of Slope Point stones. This stone is only 3 cms long and 1 cm wide. Because of its smallness, I didn’t completely smooth it before putting it into polish, doing only one week in 400 grit before a pre-polish and pro-polish

Friday 21 May 2021: Three small tumble-polished stones from my first (and so far only) fossicking visit to Slope Point (southern-most piece of land of the South Island), collected in early March, finished polishing yesterday.