Rocks From A Local Stream

[**sarahp**]

As the title says really - I grabbed a handful of rocks whilst out with the dogs this morning. My idea was to silicone them together to make a hidely hole. Will they be ok do you think? They came from a fast moving, crystal clear stream in the New Forest?

Thanks

 

[The-Wolf]

check the link in my signature

 

[**sarahp**]

check the link in my signature

I already did before I posted but I couldn't identify my rocks LOL!!! May put some vinegar on them though when I get them out of the car!! If I do and it doesnt fizz is that a 'rule of thumb' that they *might* be ok?

 

[GerardK]

I put my rocks in a bucket and poured on boiling water to sterilise and clean them.

 

[Meds081603]

I put my rocks in a bucket and poured on boiling water to sterilise and clean them.

The only advice I can offer is do not boil the rocks themselves. You never boil rocks found in water as they often have water pockets trapped in them. When the water in the rock heats up it can cause the rock to shatter sending rock fragments everywhere.

 

[ArauraDiscus]

I put my rocks in a bucket and poured on boiling water to sterilise and clean them.

The only advice I can offer is do not boil the rocks themselves. You never boil rocks found in water as they often have water pockets trapped in them. When the water in the rock heats up it can cause the rock to shatter sending rock fragments everywhere.

I don't know what rocks your talking about other than pumice, but the only ones that you can get through in a river are normally your common river rocks that are smooth and thick. Porous rocks or rocks that foster precious gems like geodes or those in the north western United States are the ones that will more likely retain air pockets. But if it's a river rock, it won't crack unless you super cool it and then super heat it all very quickly.

 

[**sarahp**]

I put my rocks in a bucket and poured on boiling water to sterilise and clean them.

The only advice I can offer is do not boil the rocks themselves. You never boil rocks found in water as they often have water pockets trapped in them. When the water in the rock heats up it can cause the rock to shatter sending rock fragments everywhere.

I don't know what rocks your talking about other than pumice, but the only ones that you can get through in a river are normally your common river rocks that are smooth and thick. Porous rocks or rocks that foster precious gems like geodes or those in the north western United States are the ones that will more likely retain air pockets. But if it's a river rock, it won't crack unless you super cool it and then super heat it all very quickly.

Thanks guys - the only trouble is I'd already boiled them for 45 mins before I read you replies BUT it was ok they didnt shatter, I have discovered my next door neighbour is a bit of a rock fanatic - she says they are just river worn flint, so according to Wolf's info they should be ok cos all he said about flint was that it could be sharp - so today I design with rocks and silicone (and probably make a complete hash ot it)

 

[Lynda B]

I soaked mine in a bucket of hot water and a little bleach to be sure I killed any little critters in there. I also did the vinegar test. Now, they look gorgeous in the tank.

 

[Meds081603]

I put my rocks in a bucket and poured on boiling water to sterilise and clean them.

The only advice I can offer is do not boil the rocks themselves. You never boil rocks found in water as they often have water pockets trapped in them. When the water in the rock heats up it can cause the rock to shatter sending rock fragments everywhere.

I don't know what rocks your talking about other than pumice, but the only ones that you can get through in a river are normally your common river rocks that are smooth and thick. Porous rocks or rocks that foster precious gems like geodes or those in the north western United States are the ones that will more likely retain air pockets. But if it's a river rock, it won't crack unless you super cool it and then super heat it all very quickly.

I have personally witnessed rocks exploding twice from being heated. I know absolutely nothing about rocks and what they are made of but I know they can explode. Years ago back in boy scouts some of the younger guys collected rocks from the potomac river for our fire pit. Both times it took less than 30 minutes of the rocks laying on hot coals for them to shatter. The first rock just had a small piece fly off but the second completely shattered and sent 2 kids to the hospital. I am not saying it happens a lot but it can happen and its bad news when it does.