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A member of the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils” mentioned to me three weeks ago that the beach near Pareora in South Canterbury was worth a look. Pareora is about seven kilometres south of Timaru South, a beach I often visit. I had a look at the area on Google Maps and decided to drop in on a beach just south of Pareora, a couple of kilometres north of the small town of St Andrew’s. I turned off the main highway onto Galletly’s Road – it’s a very short drive down that road to a freedom camping area right next to the beach. When I arrived at 11.15 am, there were a small number of buses and campervans making use of it, some of them sporting Gypsy Fair signs. A sign warns that an old landfill used to be located at the back of part of the beach. And there are some railway iron posts sticking out of the stones in front of the beach entrance.

Parked at the entrance to St Andrew’s Beach.

Sign at St Andrew’s Beach.

I spent an hour on St Andrew’s Beach. The wind was cool, the temperature about 12 degrees, and it was mainly cloudy. There are a lot of grey stones on the beach. Initially I didn’t spot much else as I walked south along the waves’ edge. I turned back north and shortly thereafter found a small piece of petrified wood. I slowed down and began to look more carefully, soon spotting a few scattered stones worth examination. I ended up spending an hour doing this. As expected, there are a lot of similarities to the stones at Timaru South – some very interesting quartzites and jaspers with the odd unusual stone.

Looking south on St Andrew’s Beach.

Looking north on St Andrew’s Beach.

St Andrew’s Beach stones.

St Andrew’s Beach stones.

Nine of my finds are presented below. The first is the piece of petrified wood I picked up:

Petrified wood from St Andrew’s Beach.

Other side of petrified wood.

This next one is my favourite find, due to its colour and texture – I think it is most likely a quartzite:

Quartzite?

Other side of possible quartzite.

I picked up this small dark stone because I thought I could see spots in it. The close-up photos suggest the “spots” could be spherulites, and maybe the stone is rhyolite – but this is speculation based on my experience with Slope Point spherulitic rhyolite. The photos are not clear enough to confirm my thoughts:

Spherulites?

This small stone has a dark brown mineral through part of it and some brecciation in another area:

Interesting brecciation.

Other side of stone.

Maybe a quartzite, also with some mineral patches and brecciation:

“Top” view.

“bottom” view.

“Side” view.

Some fine mineral lines in this find which look like epidote green:

Fine traces of epidote in this stone?

Other side of stone.

A smaller stone with a little more of the mineral through it:

I think this one could be jasper but I am not sure:

Jasper?

Other side of stone.

Finally, a dark green quartzite of a type that I have found before along the southeastern coast of the South Island:

Quartzite.

Part 17 reports on finds from Ward Beach, the day before I arrived back home in Whanganui. An Index to this Series is here.

This is a slight expansion of my letter “P” contribution to the current weekly Alphabetical Series in the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils”. In the 2021 version of this Series I posted “P is for Planet in a Pebble” , partly a reference to the title of a book published in 2010 by the Polish geologist Jan Zalasiewicz, sub-titled “A Journey into Earth’s Deep History”.

P is for Pink

Pink thulite stone found on Gemstone Beach.

The thulite stones on the Te Waewae Bay coast in Southland often have clouds of intense pink in them, due to the presence of magnesium. I found this small pink thulite on Gemstone Beach on 3 August this year. It also features in the TumbleStone 2026 Calendar, in the month of March which has six pink stones (it is Stone Six). Thulite is the national gemstone of Norway where it was first discovered in 1820. As Wikipedia notes, it is named after the mythical island of Thule in the belief that the island is Scandinavia. See “January 2022, Stone of the Day #5 – A Little Pinky” for a different variety of thulite and some specimens from Te Hikoi Museum in Riverton Aparima.

The next Post in this Series is “Q is for Quartzite”. An Index for this Alphabetical Series is here.

Gemstone Beach, in front of the carpark.

Gemstone Beach, near the Taunoa Stream.

Te Waewae Bay coast beach.

Gemstone Beach stones.

Stones 1 to 10, the larger ones.

Stones 11 to 20.

Stones 21 to 30, the smaller ones.

Relative size of Stones 1 and 30. $2 coin is 2.8cm across.

In this Series, I present 30 recently polished stones from Gemstone Beach/Te Waewae Bay. They illustrate the great diversity and beauty of the pretty stones of this beach, as well as some of the challenges a tumble polisher faces to obtain a completely smooth and well-polished stone (if that’s their aim). These 30 stones were selected from the smaller stones from batches tumbled in two 3lb barrels. Part 1 described Stones 1 to 5, with the following Parts dealing with another five stones each. The five stones featured here are the final five, and are the smallest of the 30.

Stone 26 caught my eye because of the small light patches on a mainly black stone.

Stone 26, Side A

Stone 26, Side B

It could be an amygdaloidal stone, like Stone 13, or a breccia, like Stones 1 and 2, or it could be a stone consisting of a variety of crystals – it’s difficult for me to be sure. It can be hard to get a good consistent polish on a stone like Stone 26 because of the variety of minerals in it, some of which might polish well and others of which may not. The close-ups a less than perfect surface, with lots of tiny blemishes.

It was the white quartz vein in Stone 27 that caught my eye on the beach on 30 April 2023 – it is the last stone in this Post. But the bands of hues of green are also attractive.

Stone 27, Side A

Stone 27, Side B

I was disappointed the stone did not finish its tumble-polish with a clearer surface.

Stone 28 is a small thulite pebble, with this type of stone’s distinctive pink. It was found on 18 March 2024.

Stone 28, Side A

Stone 28, Side B

Thulite is the national gemstone of Norway where it was first discovered. As Wikipedia notes, it is manganese that is the source of the pink colour. A thulite stone was January 2022, Stone of the Day #5, and that Post includes a photo of specimens from the Riverton Aparima Museum. Three thulite stones from Gemstone Beach appear in this Post (Stones W69, W70 & W71).

Thulite stones are usually very attractive and often have areas of swirling pink. However, some of them fail to tumble polish well, not taking a shine at all, and sometimes the material making up the stone can be a little crumbly. Stone 28 has a number of small rough areas attesting to these problems. Overall, it is a disappointing outcome.

In contrast, Stone 29 has tumbled very well, especially Side A. This is a variety of orbicular or poppy jasper with hematite (Stones 16 and 20 are also hematite jaspers, but not orbicular).

Stone 29, Side A

Stone 29, Side B

The orbs are not as well formed as in these two otherwise very similar stones, September 2021’s “O is for Opaque Orepuki Orbicular Jasper” and January 2022 Stone of the Day #4. Further poppy jaspers feature in this Post and this Post. Orbicular jasper is a variety of jasper which contains orbs or spherical features. Mindat states it is “a highly silicified rhyolite or tuff that has quartz and feldspar crystallized into radial aggregates of needle-like crystals forming orbicular (spherical) structures”. There are some white blemishes at the bottom right of Side B which look like tiny flakes of something – not sure whether they are remnants of the polish or, probably more likely, of some mineral like mica. Apart from these, Stone 29 has turned out very smooth and clear, largely due, I think, to the suitability of hematite jasper for tumbling.

Finally, Stone 30 is a very fine-grained light green stone with white shapes in it.

Stone 30, Side A

Stone 30, Side B

It has tumbled smoothly though has not taken a significant shine. I’m tempted to guess that it is a mudstone, such as argillite, with maybe epidote turning parts of it green. The white shapes do look like milky quartz crystals in colour but they lack sharply defined boundaries that usually come with such.

This brings this Series to an end, exposing the flaws in polished stones that can become apparent under close scrutiny. It provides a balance to those many Posts that often show gorgeous well-polished stones or unpolished wet stones where the water fills in and hides tiny scratches and holes.

The first Post in this Series is here.

TumbleStone Blog, as viewed on a laptop.

A stony beach. Ward Beach.

4lb rotary stone polisher, manufactured by Lortone, USA.

Draft of a page in TumbleStoneTwo.

For the past few months, I have been trying to think of ways of presenting the information within TumbleStone Blog in a more systematic and accessible way. This was prompted by a number of questions that arose in my mind. For example: How easy is it for someone to find an introduction to Gemstone Beach on my blog? How would someone interested in a particular stone, like orbicular jasper, be able to find the Posts that refer to it? For a beginning tumble polisher, how would they be able to find useful information on my blog? There are some Posts that provide a good introduction to a topic, or a good overview of it, but they get buried in the chronological layering of Posts. Furthermore, the “Categories” tags for topics down the righthand side of the Blog don’t discriminate between introductory Posts and Posts that might simply include reference to the topic. Using the “Categories”, each Post so tagged is shown in its entirety and it can be daunting to read through them all. The “Search” function (just below the banner on the right, near the top of each Post) brings up all the Posts using that word, and in abbreviated form, so that can be an improvement. But the mobile phone version of the Blog does not show the Categories list or the Search function. And Google doesn’t always solve the problem either.

So, just recently, I decided to try to develop a website within the blog to overcome these problems and make my material more accessible and useful. A home page will be the key – it will provide links to three main sections, Fossicking Beaches, Beach Stones, and Tumble-Polishing. Links will then be made to different beaches that I know well, to beach stones I have some familiarity with, and to information about tumble polishing beach stones. All of this will reflect my own experiences, the range and limits of my knowledge and understanding, and my own preoccupations and biases. Lists of relevant TumbleStone Blog Posts will be compiled, along with the re-packaging of Blog information and the preparation of new material. All of this will take time – it is a project in progress, with newly constructed pages posted from time to time, interrupted by the distractions of fossicking trips, tumble polishing, and everyday life.

Glimpses of drafts of eight of the “TumbleStoneTwo” pages I have been working on are provided below. The first (see below, left) is the top part of the current draft of the home page, with the key function of the page being to provide links to the three main sections – Fossicking Beaches, Beach Stones, and Tumble-Polishing. The second (below, right) is part of the main page for “Fossicking Beaches”, with links envisaged at this stage to nine beaches (or areas) that I know well. These are, in alphabetical order, Birdlings Flat, Gemstone Beach, Kaikoura Coast, Kakanui, Leithfield Beach, Riverton/Aparima, Slope Point, Timaru, and Ward Beach.

Below (left) is the main page for Gemstone Beach. One of the links on that page will be to a page about Gemstone Beach in the context of the Te Waewae Bay coast (below, right).

One of the pages on Birdlings Flat will list Blog Posts on my fossicking experiences at that beach (below, left). It is intended that the main Beach Stones page (see below, right) will link to pages on types of stones that I have collected and polished, that I have found on the nine beaches mentioned earlier.

The first beach stone I have been working on for TumbleStoneTwo is hydrogrossular garnet:

I will probably post the Home Page sometime over the next few days and then add other pages progressively over time as they become available.

Today I drove from Palmerston to Kakanui, both towns in North Otago. I first visited a small beach near Moeraki Village then took the opportunity to go and see the Moeraki boulders. Next, after turning off the main road at Waianakarua, I visited the Waianakarua River mouth and All Day Bay, before ending up at my usual beach two kilometres north of Kakanui. The Stone of the Day comes from the Kakanui beach, found towards the end of the hour I spent there. It is a small agate of an unusual dark colour:

Stone of the Day #22, from a Kakanui beach.

The white “frosting” on it is, I believe, caused by weathering. The stone is about 2 cms long. I have not found many agates on this beach and they tend to be much lighter in colour.

Other side of Stone #22.

Earlier in the day, I stopped off at a small beach near Moeraki Village that I have visited twice before, in March 2021 and June 2021 (see the entries for Monday 8 March here and Monday 7 June here). If you avoid the seals (you need to be on the look out for them to avoid close encounters), you can sometimes find some interesting pieces of chalcedony/agate here. Today was no exception:

The small beach near Moeraki Village.

I saw seven large seals on the beach, so I restricted my movements.

A large piece of chalcedony/agate – about 5 cms by 5 cms.

A smaller piece.

Ialso collected a few pieces of this kind of smooth stone – not sure what it is.

Next stop was the Moeraki Boulders which I last visited four years ago, as recorded about half-way through this Post. I noted in that Post: The boulders are large spherical rocks, [septarian] concretions that have been exposed through shoreline erosion from coastal cliffs. They consist of mud, fine silt and clay, cemented by calcite. The degree of cementation varies from being relatively weak in the interior of a boulder to quite hard at its outside rim. The boulders are cracked and eventually fall apart after having been exposed for some time.

The Boulders are popular with tourists.

Not as much of them was showing above the sand compared to four years ago.

The boulders emerge from the cliffs as they erode.

The boulders are large septarian concretions.

The segments of broken boulders expose calcite crystals.

The Waianakarua River mouth is sign-posted from Waianakarua Road. I have often thought about checking it out as I drive past on my way to Kakanui. Today I took 30 minutes out to do so. I found a nice stone that looked like petrified wood though I am yet to be convinced it is. I also saw a few rocks of a type of porphyry stone I find at my usual Kakanui beach – a polished one was January 2022, Stone of the Day #26.

Waianakarua River mouth – low flow at present.

I chose not to drive down the rutted bumpy track, walking the few hundred metres to the river.

This looks like petrified wood but may not be.

I saw quite a few of this type of porphyry, which occurs as more rounded stones further north at my usual Kakanui beach.

I had a brief stop at All Day Bay before going on to my usual Kakanui beach, arriving about 2 pm and spending an hour there.

Beach two kilometres north of Kakanui.

It was mid-tide and not a lot of stones were being wet at wave’s-edge but I was able to find some of the types of stones that regularly bring me back to the beach. These include the jaspers…

This type of jasper does not always take a polish.

Also known as limonite prase.

Also known as limonite prase.

…and the quartzites and fossil sea floor stones.

Tumbling this stone is likely to reveal tiny fossils in it.

Not sure what type of stone this is. Very smooth and very gorgeous.

I will be returning to this beach tomorrow.

The first Post in this Series is here. The Index to all the Posts in the Series is here.

This stone is a light coloured argillite with trace fossil markings on it. It is another stone from the 22 December 2021 batch that Stones #19, #20 and #23 came from. Trace fossil markings can sometimes be difficult to see in photos so I have provided darker and lighter versions of some of the close-ups:

Close-up A.

Darker version of Close-up A.

Lighter version of Close-up A.

Close-up B.

Darker version of Close-up B.

Lighter version of Close-up B.

These traces were likely left in ocean floor sediment about 250 million years ago, probably by a small burrowing animal, some kind of worm or shellfish. Some of the traces look like they may have started as ripples in the surface sediment left by a fish swimming close by. Sometimes the traces can be seen on only one side of the stone, and if appearing on both sides (if the stone is relatively thin and flat) they can be quite different.

Other side of Stone #24.

Argillite tends not to take a high polish and, in order to preserve the traces, I tend to start with only a 400 grit tumble before polishing.

For more information on TumbleStone Blog about these trace fossils, see Photo-Book “The Trace Fossil Stones of Gemstone Beach”; the Series of Posts that begin with The Fossilised Worm Cast Stones of Gemstone Beach and Riverton – Part One: Initial Identification; “I” is for “Ichnogenus Protovirgularia”; and “U” is for “Unusual Variations of Trace Fossil Stones” and “V” is for “The Chevron Shape of Trace Fossils”.

The Index to the January 2022 Stone of the Day Series is here.