Interesting...smokey quartz on petrified wood. Quartz gets "smokey" thru radioactive "buring" of the silica. Your piece probably got "burnt" from the carbon-decay when the wood got petrified. No worry, it's not "hot"...just indicates that it was exposed to it.
As for collections...books, rocks,fossils, Classic Illustrated Comics...most of which are in storage & need to have someone else collect them.
I could only afford a small piece, but the big pieces were absolutely amazing!
I hope to get back to Sedona sometime in the future as I would love to get a larger piece for only $$$ major bucks...