New to Forum with Rock Identification assistance wanted.

[Kcraven]

Hey everyone, I have been browsing around the internet for an Australian forum where people may have decent knowledge on rock identification. I believe that it is some for of lava rock but I am not 100% sure. Unfortunately I have no idea where it is from either.

As you can see it almost looks like there are other little stones in this rock. Also, on the back it looks like maybe some volcanic ash could be in there.

I realize this is not a geology forum however its worth a try to see if someone knows what it is.

Kind regards

Adam

 

[WalnLiz]

Looks very much like a piece of water weathered Basalt to me.

 

[Kcraven]

Hey WalnLiz,

Thanks for your reply! I have looked on google images and it is still really hard to tell. here are a few more close ups.

Thanks for your assistance so far

Kind regards
Adam

 

[Metamorphic]

Was thinking same Wal.

Im guessing a mixed grain, dark in color and its low Silica (quartz) level all points to Basalt.

If im wrong on the grain, and is actually a bit more course, no quartz, medium to dark in color, its possible its Diorite?

Good Luck with the search Craven

Regards

Edit> with new pics now i see specs of Silica? Definite course grain so Gabbro or Peridotite are options!

From which area??

 

[Heatho]

With the closeup it looks like Sandstone to me.

 

[Kcraven]

Thanks everyone for your replies. The only other information on it I can give is that it is EXTREMELY heavy. I was told by someone it could be red scoria rock?

Thanks for your assistance

 

[Heatho]

It can be difficult to get a true ID on rocks without measuring grain sizes and other features. Even a Geologist would be guessing from a photo. Did you find it near a beach? We get a few rocks similar to that on or below the headlands around here.

 

[Metamorphic]

Heatho is correct, very difficult from pics and its only a guess.

Best way to try and narrow the odds would be to perform a hardness test (scratch test).

You get the idea, use any of the items on the right to try and scratch the rock.

Start with your fingernail and move up if needed.....The item that is successful in scratching it, should be close to its hardness scale!

Its mainly to test 'which mineral', but can give more info on any rock for further investigation.

Post back results.

Cheers

 

[SWright]

G'Day All

Geological advice with disclaimers! Depending on where you found it. I would say it is a weathered (by waater) bit of ferricrete. This is a type of rock formed when iron in solution invades a stranded river bed. It is dormed in a similar process as calcrete and silcrete. It is often as hard as steel and very heavy.

Araluen

 

[Lefty]

Whatever it is it'll look great in the garden

 

[Kcraven]

Thanks Araluen,

Its is extremely hard and heavy. I Haven't done the scratch test yet. Was going to use in an aquarium actually and Purchased off someone a while back. Unfortunately I have no idea where it is from and nor did he. Makes it rather difficult to get it identified.

Thanks for your help