Carving hard stone

[Sky Higgins <sky.higgins@xxxxxxxxxx>]

Hi everyone,

I have found a piece of stone on a beach in Cumbria, UK. I have had a go at
carving it, but it is excessively hard - I could hardly make a mark on it,
and sparks kept flying off.

Maybe the geologists out there can tell me what it is. It is very heavy for
its size, very dense. It is a darkish red, with swirls  and blobby bits of
blue, turquoise and green in it. It looks like it might take quite a high
polish. It is sea worn, and since I can't chip it I don't know what it's
like on the inside.

As far as carving it goes, do I need different tools? I do have access to
power tools, diamond bladed cutters etc, but I prefer working with hand
tools. Are there special chisels for very hard stone. I work mostly in
sandstone, and softer limestones so I am quite at sea here.

I would really like to carve this piece, it looks like it has a lot of
potential, and I am getting bored of sandstone, so please point me in the
right direction.

Thanks, (in anticipation)

Sky