Alert Level Two, Wednesday 20 May – Stone 4, Polished Cloudy-Green Stone from Riverton

I found this stone on the Back Beach, Riverton, but I am unable to identify it. It has a couple of small patches of white quartz in it, and the close-up views suggest it may be a kind of stained quartz. One of its significant features is the cloud of green found mainly on one side. It has polished well, with just one small rough area close to the largest white quartz patch. 

Close-ups of the stone reveal characteristics of its quartz make-up and its green staining:

 

Beginning of Alert Level Two, Thursday 14 May – Stone 1, Quartz from Gemstone Beach

To mark the move of New Zealand to Covid-19 Alert Level Two from Level Three, I am posting a Stone of the Day. This is despite today being a Thursday, and this series being posted on Mondays, Wednesdays and Saturdays. But I deem this to be an important day, with the lifting of a number of restrictions. And this is a worthy stone for the day. New Zealanders have waited patiently for Level Two for more than one and a half months.

I found this stone on Gemstone Beach last year and finished polishing it just a few days ago. It is a white quartz stone. At the beginning of my stone collecting, about four years ago, I used to collect a lot of white quartz stones. They catch the eye on the beach, standing out because of their brilliant whiteness. I found that my eye was automatically drawn to them, at the expense of other stones.  I now have a nice collection of polished white quartz stones. But after a while I stopped collecting them, resisting their allure so that I could focus on other types. However, every now and then I come across an exceptional white quartz, worthy of adding to the collection bag.

This white quartz stone is exceptional for three main reasons, size, shape and clarity. First of all, it is a largish stone, at the boundary of the size that can easily be tumbled in a 4 lb barrel. I recently purchased a 12 lb barrel, mainly to be able to polish larger stones. This enabled me to polish this stone without trouble.

Secondly, the stone is pendent-shaped, a symmetrical elongated oval. This is unusual, most quartz stones being asymmetrical in shape unless they are spheroid. Thirdly, this stone is unusual due to the amount of clear quartz in it. The whiteness in quartz is caused by the presence of water, giving rise to white cloudiness. The vast majority of beach quartz is fully white. This stone has some white but has just as much clear quartz, making it translucent and giving it a striking appearance.

There are two “imperfections” in the stone. On one side there is a scarf of percussion, a plane of breakage into the stone a small way. And there are a small number of tiny black specks embedded within it.

Another Visit to Birdlings Flat, Late June 2016 – Part Three: Seven Types of Stones Collected

During the six to seven hours spent at Birdlings Flat and nearby beaches during two and a half days at the end of June, I collected just over eight kilograms of stones. These consisted of a number of different types of stones. After my two previous visits, I had a good idea of what I was looking for, based on the results of some tumble polishing as well as my own preferences. There are many greywacke stones on the beach, the common grey beach stones of New Zealand, as well as a wide range of other types.

Following are listed the seven types of stones I collected during this visit:

Yellow-patterned Quartzite; Red Jasper; Agates; Green (Quartzite?); Patterned; White Quartz and Other Light-Coloured; Others.

Yellow-patterned Quartzite – This can easily be found at Birdlings Flat and is perhaps my favourite stone from there. I discovered a small boulder of it, that filled both my hands – which I had to leave at the beach. I have brought home at least two hand-sized specimens. There are a number of subtle colour variations of this stone, the best seeming to be a clear to light coloured quartzite with curtains or swirls of “gold foil” throughout it. The intensity of the gold/yellow can vary from stone to stone as can the patterns inside it. During this trip, I sought to collect stones exhibiting these variations. 

 Red Jasper – Red jasper stones can often be found on South Island beaches. They are reasonably easy to find at Birdlings Flat, where they can be of good size and quality. Many jasper stones have silica veins, sometimes bright red veins as well, and some other mineral staining can be present. They can be brittle, with chips and pits, making them difficult to smooth and polish.

 Agates – Birdlings Flat is well-known for its agates. A wide range of sizes, shapes and types can be found. It took me a while before I learned to spot them. The best way is to look towards the sun and your eye will be drawn to the light shining through them, even amidst a whole mass of other types of stones. On this trip, I found my largest agate so far, and a very small one with a green staining.

Green (Quartzite?) – One of the interesting types of stones to be found at Birdlings Flat is green and I suspect is a type of quartzite. Again, there is a great diversity of them, from pale green through to lime green through to darker greens. I find them quite attractive and relatively easy to spot.

Patterned – I find myself drawn to even greywacke stones and other grey (or common coloured) stones if they have veins of white quartz through them or if they display layer patterns.  

White Quartz and Other Light-Coloured – Going through the stones I collected, I find there are a number of white quartz stones and other white or light-coloured stones. These tend to catch my eye on any beach, standing out from the sand or the predominant grey of the most common stones on South Island beaches. I have learned to be more restrained in my collection of white quartz as it is easy to spot it and can soon mount up in the collection bag.

  Others – What’s left in my collection bag after the rest have been taken away: 

White Quartz Stone-Collecting at Hokitika

Yesterday I visited a beach just south of the Hokitika River mouth on the West Coast of the South Island. It was raining and cold, a south-west wind blowing in over the sea. This is a beach where the sea is advancing, where the land is being eaten away when the tides are high and the weather stormy. Access is by a road that heads towards the local golf course – a vehicle-track then turns off just past the bridge over the Mahinapua Creek. The track ends abruptly at the coast – the stretch that runs parallel to the sea is being washed away. 

I walked along the beach, finding plenty of stones scattered across the sand, amongst the driftwood and remnants of flax roots. There are places where drifts of stones stretch down into the surf. The owner of the Annabelle Motel, where I was staying in Hokitika, told me this is one of the beaches where the people who make stone mats collect their raw materials.

The outstanding stone on this beach is white quartz. This type of stone is common in many places in the South Island and I found many varieties of it here. Some seem banded, some have inclusions of colour, some are pure white.