What type of rock is this?

What would be the probable range of ages for this axe?
I’m guessing that it would be hundreds to thousands of years old.

Ian said:

Not a very good one. Looks more like a left handed screwdriver.

Ian said:

What type of rock is this?

What would be the probable range of ages for this axe?
I’m guessing that it would be hundreds to thousands of years old.

We have older gound edge axes in Australia than virtually anywhere else.

>We have older gound edge axes in Australia than virtually anywhere else.

It’s not ground it’s knapped.

Ian said:

>We have older gound edge axes in Australia than virtually anywhere else.

It’s not ground it’s knapped.

Yeah but that’s the point. Even though knapped knives were still in use when white men arrived, knapped axes are exceedingly rare in all but some parts of northern australia. I’ve picked up knapped knives made from beer bottle bottoms.

It looks to be a hornfelsed or low-grade regionally metamorphosed, fine- to very fine-grained, possibly volcanigenic sandstone. But I’d need to look at it with a hand lens to confirm.

Some of the breaks in the rock seem to be very recent – maybe less than 50 years. It may not be a knapped tool.

I could have a look at it for you. I’ll be going by your way after Easter.

Michael V said:

It looks to be a hornfelsed or low-grade regionally metamorphosed, fine- to very fine-grained, possibly volcanigenic sandstone. But I’d need to look at it with a hand lens to confirm.

Some of the breaks in the rock seem to be very recent – maybe less than 50 years. It may not be a knapped tool.

I could have a look at it for you. I’ll be going by your way after Easter.

It looks to have been used for grinding or perhaps as a hammer stone, on the back. If a knapped axe, it was a failed one.

That’d be great Michael. It’d be good to see you.

I know bugger all about geology or archeology.

Hornfels (German, meaning “hornstone”) is called so because of its exceptional toughness and texture both reminiscent of animal horns. These properties are due to fine grained non-aligned crystals with platy or prismatic habits. Hornfels is the group designation for a series of contact metamorphic rocks that have been baked and indurated by the heat of intrusive igneous masses and have been rendered massive, hard, splintery, and in some cases exceedingly tough and durable. Hornfels rocks were referred to by miners in northern England as whetstones.

Most hornfels are fine-grained, and while the original rocks (such as sandstone, shale, slate, limestone and diabase) may have been more or less fissile owing to the presence of bedding or cleavage planes, this structure is effaced or rendered inoperative in the hornfels. Though they may show banding, due to bedding, etc., they break across this as readily as along it; in fact, they tend to separate into cubical fragments rather than into thin plates.

The most common hornfels (the biotite hornfels) are dark-brown to black with a somewhat velvety luster owing to the abundance of small crystals of shining black mica. The lime hornfels are often white, yellow, pale-green, brown and other colors. Green and dark-green are the prevalent tints of the hornfels produced by the alteration of igneous rocks. Although for the most part the constituent grains are too small to be determined by the unaided eye, there are often larger crystals of cordierite, garnet or andalusite scattered through the fine matrix, and these may become very prominent on the weathered faces of the rock.

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Ok. Thanks

Hornfels slate is the material used in the 20 ooyurkas found in FNQ. It is all over finely ground and polished in all 20 instances.

>It looks to have been used for grinding or perhaps as a hammer stone, on the back. If a knapped axe, it was a failed one.

Well there are hand axes and there are hand axes. This is one.

Ian said:

>It looks to have been used for grinding or perhaps as a hammer stone, on the back. If a knapped axe, it was a failed one.

Well there are hand axes and there are hand axes. This is one.

:)

Ian said:

Hornfels …

I don’t know what hornfels looks like, but this rock looks to me a bit like quartzite. And I know that quartzite has been used to make hand axes.

Quartzite is what you get if you turn sandstone into a metamorphic rock, and is common around near where I used to live.

https://en.wikipedia.org/wiki/Quartzite

Hornfels … or Quartzite

…something metamorphic

Can you come back with an answer after MV has visited? I’d be interested. We are volcanic here and it’s easy to pick up bits of bluestone that look like an axe/blade but are actually just bits that broke off a stone.

Yeah, I will certainly follow this up.

There are a few different types of rock known as “bluestone” I think.. MV can probably clarify.

This area is thick with signs of fairly recent Aboriginal habitation. I was helping a mate dig holes for footings a couple of hundred metres away from the creek and we kept hitting charcoal patches at about 400 mm down. In one I picked up a small (50 × 20 × 8 mm approx) neat basalt flake coming to a sharpish edge.. would have been a handy kitchen or pocket knife (if they had kitchens or pockets :)

Ian said:

Yeah, I will certainly follow this up.

There are a few different types of rock known as “bluestone” I think.. MV can probably clarify.

This area is thick with signs of fairly recent Aboriginal habitation. I was helping a mate dig holes for footings a couple of hundred metres away from the creek and we kept hitting charcoal patches at about 400 mm down. In one I picked up a small (50 × 20 × 8 mm approx) neat basalt flake coming to a sharpish edge.. would have been a handy kitchen or pocket knife (if they had kitchens or pockets :)

Yep. There are lots of knives to be found.

As Buffy pointed out, an inexperienced eye can make a lot of broken stones look like an axe. This looks more like one of those than the real thing.

roughbarked said:

Ian said:

Yeah, I will certainly follow this up.

There are a few different types of rock known as “bluestone” I think.. MV can probably clarify.

This area is thick with signs of fairly recent Aboriginal habitation. I was helping a mate dig holes for footings a couple of hundred metres away from the creek and we kept hitting charcoal patches at about 400 mm down. In one I picked up a small (50 × 20 × 8 mm approx) neat basalt flake coming to a sharpish edge.. would have been a handy kitchen or pocket knife (if they had kitchens or pockets :)

Yep. There are lots of knives to be found.

As Buffy pointed out, an inexperienced eye can make a lot of broken stones look like an axe. This looks more like one of those than the real thing.

in this image. My first instinct was to say, it is a rock. It isn’t an axe. Not a lot has changed. The apparent grooves may be from natural erosion like this surface was grinding on something but one also sees marks similar to this where edges have been ground on stones. This could be a fragment of a grinding stone?

I don’t think has been used as a grinding stone.

The first image shows the 2 natural or unknapped sides.. the groove is naturally formed. The other 3 show what appear to be knapped surfaces.

Ian said:

I don’t think has been used as a grinding stone.

The first image shows the 2 natural or unknapped sides.. the groove is naturally formed. The other 3 show what appear to be knapped surfaces.

Looks very basic and possibly used to chop into sedges and other tough fibrous vegetation.

bump.

I mentioned the other day that we get chips off the basalt rocks around here that look sort of axey. There are lots of rocks here, we are on the side of a scoria cone volcano. In our front garden is a pile of rocks the contractors dug out of the trench when they re-did the cabling in our street. I’ve moved a lot of them around the garden, but this lot defeats me so far. One day, when I feel really strong, I might move them a short distance…

There are rocks with little bubbles and rocks with bigger bubbles and various colours. The “native” scoria up on Mt Rouse is red.

I have collected some of the flat flakes to use as a top for my small filled area along the fence in the chook run:

Some are biggish/tomahawk size, and some are smaller, palm size.

They don’t look napped, although sometimes the edges are very sharp. I know from whacking stones with spades that the basalt flakes quite easily to produce these things.