When I was in grammar school, a girl brought in a glass mayonnaise jar filled with mercury, probably about 20 pounds worth. Her father donated it to the school for the science class. Wouldn't you know it, some idiot kid dropped the jar while trying to put it on a shelf. There was mercury all over the place, little puddles of mercury rolling all over the floor gave everyone a big laugh. The teacher had us all use pieces of thin cardboard to scoop up the mercury off the floor and put it into another container, meanwhile we were having a ball playing with the stuff! Eventually we got about 90% of the mercury picked up, but for months we would spot little blobs of it in the class room or in the hall outside of the science room. There was no HAZMAT, no evacuation, etc. Now while this happened almost 50 years ago, I know that room is still in use and I don't believe that it was ever decontaminated. If that happened today you can bet that that whole school would be shut down for months! Times have certainly changed.
About 10 years ago, a friend of mine bought about 25 1 lb. sealed bottles of triple distilled dental mercury at an estate sale for something like 20 bucks for the lot. He hit the jackpot selling the bottles individually on ebay, the bottles selling for anywhere from #100. to $185. EACH! He sold about 6 bottles before ebay would not allow it to be sold anymore. After that, he tried to sell the mercury to anyone who might buy it, but found no takers. He then tried to sell it to a scrap dealer, again no takers. He even tried to bring it to a hazardous waste dump. Even They wouldn't take it. I think he eventually gave it away for free, but I don't know what they did with it.