i found this about about 15 years ago when i was a child. i came across it the other day with my daugther.
anyway, i was wondering if someone could tell me what sort of rock or crystal it might be. also it looks like there might be lots of small bits of gold in it, but im not sure if it could be real gold. i also weighted it and it was just under 10kg so its got a good weight to it.
The main mineral is quartz.
There is a smaller-grained greenish mineral, too; it may be epidote, chlorite or something else; really can't tell without a microscope.
The golden spangles are probably pyrites.
The more common sparkles are just the light reflecting off crystal faces.
It is a nice specimen, of a sort formed in an open vein/cavity. We know that because of the well-formed crystal faces. Given time, the precipitation process could have filled the vein/cavity, whence all those nice faces would have been lost, as they grew into others 'coming the other way'.
It reminds me of a piece I collected on the coast in western Ireland around 1977. Initially, it did not look very promising - I was poking around in an open vein a few inches wide, largely filled with wet grey mud. But I noticed a few sparkly points sticking through the mud, and was able to chisel a chunk off. When I washed it in a rock pool, the mud slid away to reveal the hidden treasures beneath.