Is this a "HOT ROCK"

[srdraftcad]

Hi Fellows

Using a Garrett-GTI2500 I detected this rock that sound very good in "All metal mode" but nothing in Discrimi. Mode. Is a black stone.

What is?

[Fred]

If the detector screams "pick me,pick me" then I call it a "Hot Rock". However it does not look like the ones I found in the Tulameen. Which reminds me,I still have to get a sample for labrat. Fred

[coinshooter]

Have you put a magnet to it? If it sticks, it's a hot rock, if it doesn't, I'd see about checking the inside with a rock saw.

[Anonymous]

Any sulfide formed and visible such as you described when pointing out the the "yellow coloring" indicates the presence of Iron. The more famous yellowish tinged sulfide is the cubist pyrite sulfide. However, not all sulfides are in cubist configurations.

Iron will make a metal detector sing in all metals mode.

The good news is that discovering the presence of a sulfide is not all bad news.

Many gold deposits and silver locations, be they gossans or deposits are heralded by locating sulfides when doing grab sampling.

Nice photo and nice labelling. Got some sophisticated graphics toys I see.
FUN FUN FUN

Keep swinging that MD

[Dave (Pa)]

If it has Quartz atached and it's not magnetic, I'd be bustin that baby open to see!

[lab rat]

Can you tell if it looks volcanic or sedimentary in origin? I have seen very dark to black rocks of both types that I would consider 'hot'. On some of the beaches here I have seen rocks of clay origin that holler in all-metal but just sit quiet in descrimination. I suspect this is caused by microscopic magnetite. Volcanic lava and porphries can also do this, but these rarely contain visible free quartz. I have never encountered sulfides (ie pyrite) that make my detector go off, but it isn't a Garrett, so there might be sensitivity differences. Sorry I can't be much more help than this without examining the rock firsthand. You might take it to a college in your area and ask the opinion of someone in their geology dept.