Kakanui – TumbleStone

March 2026 Stone Collecting Trip – Part 15, Finding Patches of Stones on Seadown Beach, Kakanui, Monday 30 March

I arrived at Seadown Beach at 3pm, just after high tide. Compared to yesterday, there were fewer stones at the south end of the beach. I decided to walk north to try to find some stone patches and eventually did so, just as I was about to turn around. It was maybe 600 metres from the roadside carpark that four or five large areas of stones appeared. These provided some interesting finds.

Looking south along Seadown Beach.

Looking north along Seadown Beach.

About 500 metres north along the beach, I spotted some stones ahead.

The patches of stones.

The stones were being wet by the waves, assisting fossicking.

It was 19 degrees, partly cloudy, with a light breeze so I didn’t need my hat and scarf. I left the beach two hours after arriving.

I picked up a number of brown stones, looking for those which contain tiny bryozoan fossils. This one turns out to be the most intriguing, looking as if it does have some tiny fossils of some kind:

One side of stone with tiny fossils.

Other side of stone.

This one also seems to have some tiny fossils in it:

Another interesting brown stone.

A small highly brecciated brown stone:

Brecciated brown stone.

A fourth stone I collected because it is brown – it has quite a different texture:

Another interesting brown stone.

Other side of stone.

Four interesting quartzites from this afternoon, all of different character:

Small colourful quartzite,

Yellow hues in quartzite.

Quartzite #3.

Different kind of quartzite, with green vein.

A brecciated white quartz:

Brecciated quartz.

Finally, I think this stone is an agate (chalcedony) but it’s not like any other agates I have found on this beach. It is opaque and contains inclusions that look like the yellow/orange iron oxide that colours many of the quartzites:

One side of agate(?), wet.

The same side dry.

Other side, wet.

Other side, dry.

Opaque when held up to light.

In Part 16, I continue my way north, stopping off at a beach near St Andrew’s in South Canterbury. An Index to this Series is here.

March 2026 Stone Collecting Trip – Part 14, Starting the Trip Back Home, A Fossick on Seadown Beach, Kakanui, Sunday 29 March

I reached Seadown Beach, just north of Kakanui, at 2pm this afternoon after a long drive from the south coast of Southland. It was raining during the first hour or two of the drive but scattered showers then dominated. At Seadown Beach, the tide was high but there were a lot of stones high up the beach, wet from the waves or from recent rain. This was especially the case among the rocks at the south end of the beach, where the stones have been piled higher than I have seen before.

Seadown Beach, Kakanui.

Looking north along Seadown Beach.

There were good pickings at the south end of the beach.

The sea must have recently been turning the stones over and churning them up because I had a very productive hour-long fossick. I found an amazing range of quartzites but a number of other very colourful and patterned stones as well, plus a piece of petrified wood.

This is the petrified wood, a relatively rare find for me on Seadown Beach:

Petrified wood.

Other side of petrified wood.

There are links to other specimens of petrified wood I have found on this beach here.

I think this next stone is what is known locally as limonite prase:

One side of this stone looks like plain quartz but the other side is far from plain:

The plain side.

The more interesting side.

A colourful orange stone with different patterns on different sides:

Another orange find, this one with some brecciation (tiny fragmentation):

These are seven of the quartzites I collected, quite a diverse lot:

I kept my eye open for the brown stones that sometimes contain tiny bryozoan fossils – this is the best candidate but I can’t clearly see such fossils in it:

And finally, an interesting mix of colours:

I return to Seadown Beach tomorrow. An Index to this Series is here.

March 2026 Stone Collecting Trip – Part 5, Stones Disappear Again on Kakanui’s Seadown Beach, Sunday 15 March

As I noted in my previous Post, yesterday the waves had washed sand away, exposing lots of stones on Seadown Beach. Today, when I arrived at 4.30pm, another change had occurred – the waves had washed tiny stones and pieces of shell over most of the stones. Even the small coves in the rocks at the south end of the beach had few stones exposed.

A beach dominated by tiny pieces of stone and shell.

Very few tumble-sized stones exposed.

The view in one of the small rock coves that usually has lots of stones on the surface.

Nevertheless, I managed to find a few stones for tumble polishing, though most of them were on the smaller side. Eight of them are featured below.

Three of my finds were small quartzites which illustrate the variety of hues from neutral to yellow:

A small very shiny stone that is also possibly a quartzite:

Small quartzite?

Other side of stone.

Two small jaspers:

First small jasper, with quartz.

Other side of stone.

Second small jasper.

Other side of stone.

And, to finish, two fossiliferous limestone pebbles:

First fossiliferous limestone.

Other side of stone.

Second fossiliferous limestone.

Other side of stone.

This was the last of my three fossicks on Seadown Beach before continuing south. My next fossick will be on Gemstone Beach in Southland. An Index to this Series is here.

March 2026 Stone Collecting Trip – Part 4, Stones Appear on Kakanui’s Seadown Beach, Saturday 14 March

I spent just over an hour on Seadown Beach this afternoon. It was warmer than yesterday, reaching 21 degrees, with few clouds in the sky. Though there was a stiff breeze so I donned my woollen hat and scarf. The state of the beach had changed significantly – a lot of sand had been removed by the waves overnight, exposing many more stones. You can see this in the comparative photos below (the first four), although the views are not strictly exactly the same:

Saturday’s exposed stones, looking north.

Friday’s sand.

Saturday’s exposed stones, looking south.

Friday’s sand.

Seadown Beach stones, Saturday.

As usual, I collected a few nice quartzites. This one I consider the most interesting visually, with many different colours and shapes:

An interesting quartzite.

Five red and/or yellow quartzites, some having an unusual patterning:

Some red in this quartzite.

Variegated yellow quartzite.

Clear patch in this quartzite.

Very light yellow.

Yellow mineral dispersed throughout this quartzite.

Two other-coloured quartzites, the first a light green, the second a very smooth white/grey/green with interesting band-like features:

Light green quartzite.

Small very smooth tri-colour quartzite.

I found two stones today that might have tiny bryozoan fossils in them – see this Post for more about them. It is very difficult to see the fossils with the naked eye so I look out for stones of a particular brown colour and then check them out by taking photos and looking at the close-ups. This is the first one:

Probably contains tiny bryozoan fossils.

Other side of stone.

and this is the second one:

Second possible stone with bryozoan fossils.

Other side of stone.

In both cases, there are small areas which look to contain bryozoa.

Three of the jaspers I found today are below – the third one was particularly difficult to get a good photo of because it has a rounded surface and picked up lots of reflection:

Finally, a small quartz stone with thin veins of colour through it:

Quartz.

I take selfies only on very rare occasions – but this is how I look now, if you’re looking for me on a beach. I recently had a haircut and beard trim, which is one of the reasons for the scarf and hat. My glasses get darker as the sun gets brighter. I am carrying my small green backpack, and I’ll often have a black cloth bag with stones in it in one hand.

JP.

JP.

A third Kakanui fossick, before moving on to the south coast, encountered changed beach conditions again. An Index to this Series is here.

March 2026 Stone Collecting Trip – Part 3, Wet Gumboots and Quartzites, Seadown Beach, Kakanui, Friday 13 March

I drove from Timaru to Kakanui today, stopping at Seadown Beach at noon. It was cold, 13 degrees, with some wind and persistent light rain. The tide was high and the beach was very sandy with few stones apparent. I had nowhere else to go until my motel became available at 2pm so I braved the conditions. I spotted some stones at the south end of the beach, among the rocks. A couple of small coves could be accessed, though a keen eye had to be kept out for the waves.

Seadown Beach, Kakanui, looking north towards Oamaru.

Seadown Beach, looking south.

The only real area of stones on the beach, at the south end.

Stones in one of two small coves in the rocks.

Today’s finds from Seadown Beach.

At one point, a wave came in a little more than I anticipated and I got wet gumboots. So I went back to the car and put on a dry pair of socks and gumboots, and resumed my wet-weather cove-enclosed fossicking. Quarter of an hour later, I got wet gumboots again! I eventually quit the beach at 1.40pm, sloshing my way back to the car though with a good collection of finds.

This is a great beach for quartzites. I found a couple of nice red ones – initially they can look like jaspers but close inspection shows that they are not, one of the clues being the clouds of mineral colour in them.

A deep red quartzite.

Another red quartzite.

More common than red are yellow quartzites here. Following are two I picked up today:

Quartzite, one of the bigger stones I collected.

Yellow quartzite with some unusual patches.

Two neutral coloured quartzites (below), the first being too large to tumble but it will be placed in the garden back home – guests will walk past it on the way to “The Stones”, our AirBnB accommodation. The second has thin misty clouds of brown in it.

The largest quartzite I collected today.

Quartzite.

This small dark stone (below) seemed to have some interesting patterns in it so I put it in my bag, knowing close-up photos would show more. I think it too is a quartzite:

Small dark quartzite?

I sometimes find small round smooth button-like quartzites, usually with white mixed in with green, blue or grey. I spotted this green one today:

Quartzite “button”.

The next quartzite doesn’t have any interesting mineral clouds but, rather unusually, it contains dendrites. Dendrites are branching tree-like or fern-like mineral formations, usually manganese oxide, that grow along cracks in rocks or between rock layers. They can easily be mistaken for plant fossils. See “D is for Dendrites”, the second of these two Posts.

Dendritic quartzite.

I found one small piece of petrified wood – I thought it was driftwood when I spotted it but I often check these out in case they turn out to be stone:

Petrified wood.

This is a dark version of another piece I found about five years ago. See this Post for some other pieces of petrified wood I have found previously on Seadown Beach.

I came across a stone of the type that looks like what is known as “plasma jasper”, characterised by the green in it:

Plasma jasper?

Finally, a small piece of fossilised seafloor, probably a kind of limestone:

Fossilised seafloor.

Other side of stone.

I’ve collected a few of these in the past and always find them interesting because of the tiny fossils in them. They are a soft stone so need only a fine grit tumble to clarify their surface – see “Kakanui Fossilised Sea Floor Stones – Only 400 Grit Tumble“.

Tomorrow sees another visit to Seadown Beach. An Index to this Series is here.

TumbleStone Calendar 2026: October – Kakanui Quartzites II

The Introduction to this Calendar can be found here. The Calendar features groups of beach stones I have collected recently, a different group each month. The stones are rough (un-polished) and usually wet, showing their colours and details. A small number of these 2026 Calendars remain for sale, with postage within New Zealand included, for $35 non-rural, $40 rural. Two Calendars to the same address cost $60 non-rural, $65 rural. Three Calendars to the same address cost $85 non-rural, $90 rural. Email me at john.tumblestone@gmail.com.

Calendar Cover, 2026.

October.

October’s Kakanui Quartzites.

The month of October features five quartzite stones from Seadown Beach, Kakanui, North Otago – another five featured previously in the month of May. Quartzite is a hard, metamorphic rock that forms when a quartz-rich sandstone is subjected to high heat and pressure over time. This process causes the quartz grains in the sandstone to fuse together, creating a dense, durable rock. One of the characteristics of most of these Kakanui quartzites is the tiny clear quartz crystals or fragments that become visible in close-up photos. Another common characteristic is the cloud-like distribution of colourful mineral throughout the stone, often iron oxide. Some of the diversity of these features can be seen here and in this Post.

Stone One (top row, left, in the Calendar) has a more subdued hue than many Seadown Beach’s quartzites, though it contains intriguing clouds of subtle colour giving a sense of depth:

Stone One, October.

Parts of the stone look like what you’d see peering through a powerful telescope into a galaxy in outer space. I found it on 23 March 2024.

Stone Two (top row, right, in the Calendar), was found on very productive fossick on 25 August 2025. I wrote in the Post about that fossick: “My favourite find today is a cloud quartzite containing different hues and some tiny black dots.” The stone is an interesting specimen for it contains four of the major Kakanui quartzite colours – grey, light yellow, orange, and red:

Stone Two, October.

The black dots are likely to be iron or manganese. The characteristic tiny clear quartz crystals or fragments are present, especially in the lighter coloured area. The appearance of clouds in a three-dimensional way is also there.

Stone Three (bottom row, left, in the Calendar) is among the darkest of the grey Kakanui quartzites I have found:

Stone Three, October.

It was collected from Seadown Beach on 27 August 2025.

The most red of the 10 Kakanui quartzites in the 2026 Calendar is Stone Four (bottom row, centre, in the Calendar):

Stone Four, October.

It would have been easy to mistake this stone for a red jasper, but the grey area would not have fitted that identification and it contains the tiny clear quartz pieces of the other quartzites from this area. As with Stone Two, Stone Four was found on very productive fossick on 25 August 2025.

Stone Five (bottom row, right, in the Calendar) is a rich yellow/orange, found on 30 March 2025:

Stone Five, October.

Yellow is one of the more common colours for Seadown Beach quartzites, though yellow quartzites can be found on beaches north of Kakanui through to Birdlings Flat. Stone Five has a more intense colour than most, though the appearance of “clouds” of mineral within it is still present.

For November’s breccia stones, see this Post.

Q is for Quartzite

This is a slight expansion of my letter “Q” 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 also posted a Kakanui quartzite though of quite a different colour – see “Q is for Quartzite Stone from Kakanui”.

Q is for Quartzite

Kakanui quartzite.

This stone appeared on Seadown Beach, Kakanui, North Otago, on 6 September 2024. In it, shades of grey form a backdrop to a dripping cascade of light yellow. I found quite a few good specimens of quartzite that day – see photos below which illustrate some of the diversity on this beach, though I have also at other times found a few red specimens:

Kakanui’s Seadown Beach, 6 September 2024, the day I found this quartzite.

Seadown Beach, 6 September 2024.

Stones and a couple of birds on Seadown Beach, Kakanui, 6 September 2024.

Twenty of the quartzites I found that day.

The one that is the subject of this Post.

Another Kakanui quartzite found 6 September 2024.

Three red Kakanui quartzites found at other times:

Red Kakanui quartzite.

One of my sources for the identification of this type of stone as quartzite is Jocelyn Thornton’s book “Gemstones” – on page 34 of the online version on “Beach Pebbles from Moeraki-Kakanui”, she shows one of these stones which she labels “Quartzite from Central Otago”. Another source is seeing a display of quartzites in the Birdlings Flat Gemstone and Fossil Museum:

Thornton's "Gemstones", page 34. www.onnaturesedge.co.nz/downloads/nzgemstones.pdf

Thornton’s “Gemstones”, page 34. http://www.onnaturesedge.co.nz/downloads/nzgemstones.pdf

Birdlings Flat Museum quartzites.

Quartzite is a hard, metamorphic rock that forms when a quartz-rich sandstone is subjected to high heat and pressure over time. This process causes the quartz grains in the sandstone to fuse together, creating a dense, durable rock. According to most definitions, quartzite is composed of more than 90% quartz (see University of Auckland Geology). One of the characteristics of most of these Kakanui quartzites is the tiny clear quartz crystals or fragments that become visible in close-up photos.

The next Post in this Series is “R is for Rhyolite” featuring a spherulitic rhyolite from Slope Point. An Index for this Alphabetical Series is here.

TumbleStone Calendar 2026: May – Kakanui Quartzites I

The Introduction to this Calendar can be found here.

The month of May in the 2026 TumbleStone Calendar features five quartzite stones from Seadown Beach, Kakanui, North Otago. Quartzite is a hard, metamorphic rock that forms when a quartz-rich sandstone is subjected to high heat and pressure over time. This process causes the quartz grains in the sandstone to fuse together, creating a dense, durable rock. According to most definitions, quartzite is composed of more than 90% quartz. One of the characteristics of most of these Kakanui quartzites is the tiny clear quartz crystals or fragments that become visible in close-up photos. There is such a diversity in the colours and patterns of the quartzites to be found on Seadown Beach that there are enough for the month of October as well – some of the diversity can be seen here and in this Post.

Calendar Cover, 2026.

May.

May’s Kakanui quartzites.

Stone One (top row, left, in the Calendar) lacks the colour that many Seadown Beach’s quartzites have, though it contains intriguing clouds and swirls:

Stone One, May.

Another variation of the grey neutral-hued quartzite can be found in this Post. I found Stone One in the morning of 30 September 2024.

A dash of yellow and red feature in Stone Two (top row, right, in the Calendar):

Stone Two, May.

It was picked up on the afternoon of 1 March 2025, along with a number of other quartzites.

Many of Seadown Beach’s quartzites are yellow. Stone Three (bottom row, left, in the Calendar) is an interesting yellow variant with light and dark patches giving the appearance of layers of clouds:

Stone Three, May.

This type of quartzite is the most attractive to my eye. I found Stone Three on 16 February 2024.

Stone Four (bottom row, centre, in the Calendar), found on 30 July 2025, has red dominating two-thirds of it – again, the colour appears in cloud-like formations:

Stone Four, May.

And Stone Five (bottom row, right, in the Calendar) has significant red throughout:

Stone Five, May.

It was 25 August 2025 that I came across Stone Five.

These 2026 Calendars are for sale, with postage within New Zealand included, for $35 non-rural, $40 rural. Two Calendars to the same address cost $60 non-rural, $65 rural. Three Calendars to the same address cost $85 non-rural, $90 rural. Email me at john.tumblestone@gmail.com.

For June’s black and white igneous stones, see this Post.

N is for North Otago Neutral-Hued Quartzite

This is a slight expansion of my letter “N” contribution to the current Alphabetical Series in the Facebook Group “New Zealand Lapidary, Rocks, Minerals, Fossils”. In the 2021 version of this Series I posted “N is for November in the Calendar” (featuring four Leithfield Beach stones).

N is for North Otago Neutral-Hued Quartzite

What I refer to as a neutral-hued quartzite, from Kakanui in North Otago.

I found this quartzite two months ago on a beach at Kakanui just south of Oamaru in North Otago – see “August 2025 Stone Collecting Trip – Part 19, A Surprisingly Productive Fossick at Seadown Beach, Kakanui, Monday 25 August”. I call this beach Seadown Beach as it starts right near where Seadown Road intersects Thousand Acres Road/Beach Road.

Seadown Beach is on a 5 km sweeping part of the North Otago coast. Source: http://www.topomap.co.nz/NZTopoMap?v=2&ll=-45.148453,170.913019&z=13

The south end of the beach last year.

Looking north along Seadown Beach, Kakanui.

Seal at the bottom of the rocky cliffs at the south end of Seadown Beach.

Hector’s dolphin, Seadown Beach, Kakanui. August 2025.

On this beach, just two kilometres out of Kakanui, I have found quartzites in a range of hues. These quartzites appear as far north as Birdlings Flat (see this Post) and I have seen a handful as far south as Gemstone Beach (as in this Post). They often turn out to have tiny clear fragments of quartz in them when I zoom in on their photos. The most common colour for them is yellow while some are red and others are brown or even nearly black.

Light yellow Kakanui quartzite.

Yellow “clouds” in a Kakanui quartzite.

Deep red Kakanui quartzite.

Kakanui quartzite with reddish brown mineral clouds.

Dark-hued Kakanui quartzite.

Multi-hued Kakanui quartzite.

A few of these quartzites are what I consider to be neutral in hue, a kind of pale grey like the stone at the top of this Post – the addition of minerals like iron oxides gives them a much more colourful character. For more examples, see “September 2024 Stone Collecting Trip – Part 4, Multiple Quartzites from Seadown Beach, Kakanui, Friday 6 September”.

The next Post in this Series is “O is for Outstanding Orepuki White Orbicular Jasper”. An Index for this Alphabetical Series is here.

August 2025 Stone Collecting Trip – Part 21, A Bridge and Other Distractions at Seadown Beach, Kakanui, Wednesday 27 August

Zooming in…

Chiton.

This afternoon I drove north to Christchurch. Before I did that, I made a last visit to Seadown Beach. It had been frosty overnight, and was only four degrees when I left my accommodation on the hill in Kakanui at 10am. However, the sun was shining brightly. When I arrived at the beach ten minutes later, the temperature had climbed to seven degrees. On the way, I stopped to take a photo of the new bridge being built over the Kakanui River. The current bridge is a narrow one-lane rickety one, and heavy goods traffic can’t use it. It was built in 1899, the second on the site, the first having appeared in in 1871. “The new replacement bridge will be a fully concrete structure, creating a single-lane suitable for heavy goods vehicles, as well as a separated pedestrian/cycle path” (Waitaki District Council, 1 April 2025). It is costing just over 11 milllion dollars and expected to be fully operational by the middle of 2026 (Waitaki District Council, 14 July 2025).

The present Kakanui bridge. Source: https://www.waitaki.govt.nz/News/Next-stage-of-Kakanui-bridge-replacement-underway

The present Kakanui bridge, with the new one being built alongside.

Bridge building works.

Seadown Beach, Kakanui, today, looking south.

The rock platform at the south end of the beach.

This morning’s finds.

Arriving at Seadown Beach, I found the tide was low enough for me to walk past the rocks at the south end to visit the patches of stones in the small bays there. I found very little of interest past the first two bays. In fact, today’s fossick was not very productive at all, certainly much less interesting than my first fossick here two days ago. I ended up with about 30 finds. I spent some time walking on the rock platform in the south of the beach, checking out any stones that might be there. I found very few stones fit for the tumbler. For a time, I got distracted by what else I saw there:

Chunky jasper rock.

Small marine mollusc, a chiton.

Chiton.

A couple of marine centipedes or isopods.

Tiny gray seaweed, maybe a marine algae.

At the end of the fossick, I got a tray from my car and filled it with water from the sea so I could photograph some of the more interesting ones – I knew the weather would be a lot less sunny after today and it might be difficult to get good photos tomorrow. Filling the tray from the edge of the waves, I glanced up and saw the fin of a Hector’s dolphin a few metres away. I spent the next 15 minutes trying to get photos of the two or three dolphins out there. I was fortunate enough to catch one of them just as it was re-entering the water after a leap.

I spotted a dolphin fin just beyond the breakers.

The leaping dolphin.

Zooming in on previous image.

The dolphin re-entering the water.

Zooming in on previous image.

Here are six of my finds from this morning. When I found the first one, I thought it was most likely what is called limonite prase in this area. The close-up photos then revealed tiny veins with what looks like a kind of agate (banded chalcedony) in them:

Limonite prase, with banded transparent chalcedony veins?

My second featured find is not like anything I have seen on this beach before. It’s a real mix of a number of different unusual elements, colours and shapes: