Garden "rock". Should I crack it open?
This "rock" weighs 16 pounds. Located in Edmonton, Alberta, Canada. Its origins are unclear. It was salvaged by my dad who got it from a construction site somewhere in the city. It has been sitting in his garden for about 15 - 20 years. We never noticed the inclusions until recently. The brown surface has a soft hardness. It doesn't come off if touched with the hand, but if run under water and scrubbed with a brush it will come off gradually as a fine sediment. Under magnification, microscopic specks of a golden colored metal can be seen, although not in great numbers. I've only seen 1 or 2 specks. I'm really unsure if it is gold or not, however I wouldn't be surprised if it were.
I'm wondering if I should crack it open to see if there is anything more interesting inside of it or if I should just keep it the way it is. Is there anything else about this that is interesting?