stone - How to cut pumice?

I've found a few pumice rocks at the beach, from the size of an egg to about a handball. I've boiled them and left them in diluted bleach for a while to disinfect and clean. Now I'd like to cut some of them into shapes which are easier to handle and just generally nicer. As someone unused to cutting rock of any kind, I wonder about the following and just generally how to handle it:Pumice is brittle, sometimes so brittle that I can break it with my hands. Can I hold it reliably with a vice or clamps?I've got an angle grinder and a small multi-to...Read more

stone - What is the purpose of the sand/gravel bed under dry-laid flagstone?

I have soil with a lot of clay in it and few stones, so it's not too hard to get level. I've got flagstone in a couple of small areas. Some of it is on a bed of gravel and some of it is on bare soil. I don't see that one is any worse off than the other. I was just curious if the sand/gravel bed typically installed under flagstone is for drainage, ease of leveling, weed control, pest control or other.....Read more

Can I use Kerdi Board instead of Cement Board to thinset natural stone tile?

I've got these split face natural stones that come in 24 x 6 panels, and I was going to install them onto Cement Board using thinset. Checking the boards out (Permabase Plus), they contain silicates which can apparently irritate my asthmatic kid (and cause cancer it seems!).Despite being more expensive, would Kerdi board work as a backer? I'd rather break my wallet than my kid's lifespan.Thanks for your help....Read more

stone - How do I break rotten boulders?

I have a lot of rocks around my house. Generally, I drill holes with a rotary hammer and then use wedges and feathers to split them. There are some that are rotten, however, and the wedge and feathers just blow out. They are massive, and breaking then with a jackhammer would take a long time. Is there another option? I think that if I could saw them or something, it would be easier....Read more

retaining wall - Stone raised garden bed on a slope

I want to build a raised garden bed with a stone wall. Height would be 1 foot. Since this will be in the front of the house I'm looking at "nice" stone, so not just concrete blocks. I will probably do something like 20ft by 4ft.I'm thinking of using stone that has that "lip" on the back to make it easy to get the back setting correct. Two main questions:Now I've done some googling around and I can't seem to get a straight answer to whether I need a foundation poured or not. I'm in Montreal so we have pretty cold winters but depending on what si...Read more