February-March 2022 Fossicking Trip: Stone of the Day #22, Small Dark Kakanui Agate

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.

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