Black basalt problems, - Hair line cracks within stone

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exoticpete
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Location: Berkshire

Post: # 91831Post exoticpete

Hi all we are doing a patio using black basalt as an edging and steps and we experiencing some major issues with the stone, when the stone is dry it seems perfect but once you put water on it to clean it hair-line cracks within the stone become apparent, am I missing something ? Stone sourced from 2 different suppliers both getting the stone from china, we are handing the stone like glass
Any advice greatly appreciated

Peter
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Tony McC
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Post: # 91869Post Tony McC

There shouldn't be hairline cracks in genuine basalt as it's a crystalline rock. Are you sure it's basalt? Got any photies?
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exoticpete
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Location: Berkshire

Post: # 91871Post exoticpete

Hi Tony many thanks for the reply, its being sold as black basalt/Granite, it would be very hard to quality control as you only see the cracks when the stone is drying out and the moisture is drawn into the cracks, I will take some photos tomorrow, despite this it still is a stunning paving material.
cheers Peter
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London Stone Paving
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Post: # 91883Post London Stone Paving

I would be very interested to see some photos of this Pete.

exoticpete
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Location: Berkshire

Post: # 91903Post exoticpete

Busy day so no photos, but I have been advised that they are not cracks but 'fissures' and do not affect the structural integrity of the stone I will endeavour to take some photos tomorrow
Cheers Peter
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Tony McC
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Post: # 91904Post Tony McC

The fact that the supplier isn't sure whether it's a basalt or a granite is worrying. Anyone with a basic knowledge of geology and/or stone supply should know this. It's aking to saying "it's a limestone/sandstone"". It's one or the other: it can't be both.

Fissures, cracks, crevices, grikes, call 'em what you will, but they are not usual in either granite or basalt.
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exoticpete
Posts: 117
Joined: Thu Feb 05, 2009 4:49 pm
Location: Berkshire

Post: # 91912Post exoticpete

Hi Tony, sold as black basalt, and the 'fissures' do not crack or open up when hit with a rubber mallet could it be a form of veining ?
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Dave_L
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Post: # 92011Post Dave_L

It could be bitmac..........it could be concrete.........:p
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London Stone Paving
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Post: # 92013Post London Stone Paving

exoticpete wrote:Hi Tony, sold as black basalt, and the 'fissures' do not crack or open up when hit with a rubber mallet could it be a form of veining ?
Post a photo Pete, so we can see.
I had a look at some of our basalt and its full of small veins which could be mistaken for cracks. A picture would help to clarify

exoticpete
Posts: 117
Joined: Thu Feb 05, 2009 4:49 pm
Location: Berkshire

Post: # 92056Post exoticpete

Hi all all will endeavour to post a photo sometime next week, mentally busy at the moment

Cheers

Peter
I wish i worked outside...

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