# What do you think about this rock



## zanguli-ya-zamba (17 Jun 2013)

Hi guys just wanted to have a feedback about this type of rock. 
Do you think the texture of this stone will be nice 




I can have exactly the same stone with the same texture, but with a greenish color like oxidized copper. 

Thanks


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## DrRob (17 Jun 2013)

Texture wise it's a lovely stone. What is it? I'm trying to work out if that's a limestone.


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## zanguli-ya-zamba (17 Jun 2013)

Hi mate I don't know at all what stone it is!
I am working in road transportation and these are stones that our drivers bring back from their trip. They use it to make "brake blocs" in case there is a brake problems. In one of my current set up I use white stones with grey veins. 

So you like the texture ?


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## Greenview (17 Jun 2013)

That is a lovely stone. What does it look like submerged in water?


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## zanguli-ya-zamba (17 Jun 2013)

DrRob said:


> Texture wise it's a lovely stone. What is it? I'm trying to work out if that's a limestone.



Here is a pic of the white stone I am talking about unfortunately you can't see it very well but at least you have an idea


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## Greenview (17 Jun 2013)

Wow, that's a fast reply to my question!


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## zanguli-ya-zamba (17 Jun 2013)

Greenview said:


> Wow, that's a fast reply to my question!


Hi green view sorry to disappoint you buy the stone you see in the tank is an other type of stone. I am out of town until Friday. What I will do for you is take the stone of the first pic and put it in my tank and take a pic like that we can see how it is when submerge !  

Cheers


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## DrRob (17 Jun 2013)

zanguli-ya-zamba said:


> They use it to make "brake blocs" in case there is a brake problems.


 


Almost certainly limestone then. Will be fine in a hard water tank like a malawi set up but will slowly dissolve in anything softer, and will mess with water chemistry.

It's doable, but that's a large rock for surface area. Not as bad as a substrate for messing with chemistry but not good in a soft water tank overall.


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## zanguli-ya-zamba (18 Jun 2013)

DrRob said:


> Almost certainly limestone then. Will be fine in a hard water tank like a malawi set up but will slowly dissolve in anything softer, and will mess with water chemistry.
> 
> It's doable, but that's a large rock for surface area. Not as bad as a substrate for messing with chemistry but not good in a soft water tank overall.


 Hi DrRob I don't think it's a limestone I will do the scratch and vinegar test when I'll be back. 
What make you think it's limestone mate ? I start worrying now lol 

Regards


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## DrRob (18 Jun 2013)

The use as brake pads. It's an old school use of limestone. That and it looked like limestone when I first looked at it.

Personally I'm a fan of limescale cleaner if you really want to be sure what something is. Less doubt about the fizz.


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## zanguli-ya-zamba (18 Jun 2013)

DrRob said:


> The use as brake pads. It's an old school use of limestone. That and it looked like limestone when I first looked at it.
> 
> Personally I'm a fan of limescale cleaner if you really want to be sure what something is. Less doubt about the fizz.



They would use as brake pads like they would use any stone or big pieces of wood that they place under a tire to be sure the truck won't escape them when they are parked lol. 

You are starting to get me worried because I have soft water and don't want my water parameter to be mess up. 

I have read in many place that if you scratch a limestone you will have a white "powder" coming out is that true ? 

What also let me think it wasn't a limestone is that is really strong. I had to use a 10 KG hammer and beat again and again to break it lol 

Thanks for the infos you are giving me.


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## dw1305 (19 Jun 2013)

Hi all,


zanguli-ya-zamba said:


> What also let me think it wasn't a limestone is that is really strong.


If it is a really hard rock you can use it even if it is a limestone, as very hard rocks must be very sparingly soluble, or they wouldn't be very hard. If you have exposed limestones in wet tropical climates you tend to get an associated "cockpit country" geology <Trelawny Geology>, with rock pinnacles, solution hollows and caves etc.

My suspicion  would be that it is Granite or Rhyolite etc. <Rhyolite - Wikipedia, the free encyclopedia>.

cheers Darrel


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## DrRob (19 Jun 2013)

Ahhh, so you mean that they use them as chocks. That's different.

I'd still drop some acid on it and see what happens, but if it's not fizzing I'm with Darrel on the granite.


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