# Slate Rock or Flint?



## Cheyd (Mar 17, 2004)

I went rock collecting back about a month ago. I've been slowly cleaning and prepping the rocks over the past month as time (and some major work projects) have allowed. Anyways, I've been chiselling some of the rocks to particular shape tonight, and have seen some sparking. I'm just concerned whether the rocks I have are reasonable to use in the tank. I collected them 2 miles east of Hartsthorne, Pittsburg County, Oklahoma. They appear to me to be a gray slate that has some quartz banding. Then again, I'm a blithering idiot when it comes to geology. There are photos of the collection site and the rocks themselves in my gallery on this site. Could someone take a look? Or provide a test or two I can perform (other then put them into a bucket and test the water after 2 weeks)?


----------



## chiahead (Dec 18, 2004)

If u want to see if it will buffer you kh u can test it in a bucket with some H2o in it then pour some muriatic acid. If it bubbles it will buffer your kh. Other than that I do not know how to test for leaking of anything else. Hope this helped you!


----------



## dennis (Mar 1, 2004)

Thats not slate, IMHO. I have never seen slate or shale formed that looked like that, although I an basing my experiences from New England, Ohio and western Pa. My guess based on where you collected that rock is that it is either limestone or possibly flint. I am definately no geologist though so my guess is based mainly on intuition. If it was flint though, it would spark alot with most hits. I have had chisels/hammers spark if the rock hit is very hard and the blow is glancing. Were you using an actual masonry chisel or something else. If you were using something else, be very careful as it might be to brittle to hit something that hard and could shatter.


----------



## Cheyd (Mar 17, 2004)

Dennis - The chisel I'm using appears to be a masonry chisel, but I'll be honest - I have no clues for sure. I live in a town of 700 people. The 2 local hardware stores don't carry masonry chisels, but one of the guys working at one found a chisel the day before out in the parking lot. They figured it was accidentally left by one of the construction crews working in the area. They gave it to me when I asked for one. So far, no shattering, and it's been hit fairly hard.

Chiahead - I guess I'll have to try the muriatic acid test. Thanks.

If anyone else has any ideas, PLEASE - Post! I'm almost ready to fill and plant.


----------



## dennis (Mar 1, 2004)

Test it with muratic acid...No fizzing and you will be fine. Go ahead and us it. AFAIK, it will not matter if it is flint.


----------



## chiahead (Dec 18, 2004)

isnt there a possibility even if it does fizz with the muriatic acid that it could potentially leak something else that may be harmful to the fauna? Just curious about this issue.


----------



## JanS (Apr 14, 2004)

I don't know the first thing about geology either, but here's a very good article about rocks in the aquaria.

Rocks in the aquaria - a geologists view

Wow, our company used to ship to Hartshorne all the time. Brings back memories.


----------

