Found mercury by luck then was offered some more !

This happened a few weeks ago. My other hobby is... everything below ground level !
Mines, bunkers, rivers, quarries, factories, caves. I like to walk endlessly in the dark mostly in search of traces of history or just the beauties of nature.

This has led me into quite interesting places (beneath the Red Square!).
That time, a friend I initiated into this (more about that friend at the end of the post) invited me to visit the basement of an abandoned physics lab. There where quite a few things that would make it very recognizable.

Suddenly, one of youngsters (20ish) said "Hey, a borosilicate tube"
Thinking it weird that someone would give such a precise description so I got interested.

With that boro tube I started scraping something off the crust that covered something that seemed more and more recognizable...
(your guesses about that tan / beige crust are welcome)

While we where still around, a friend yelled he had found an odd bottle.

Pretty certain of what it would be: a 35kg steel bottle for storing mercury.
Empty sadly... but there still was the very recognizable silvery color at the bottom sticking to something.

Since I didnt have a syringe, I could not collect this mercury that I didnt need anyway.

But the fun isnt over !
Later on, in another place with other people I was still happy that that happened and was talking about it.
One of the guys there that I didnt know told me that he had about two kilograms of mercury in a small vial that he didnt know what to do with. He had wanted to get rid of it for the last 40 years.
Of course, I offered to help and should see him in two weeks

I'll update then.