I had two old mercury thermometers. Now there is one. Outdoors, I broke open a mercury thermometer and placed the majority of the mercury in a vial. To seal the vial, I placed petroleum jelly around the lid and tape over the petroleum jelly. Unfortunately, the subsequent playing with the mercury bead dislodged quantities of the petroleum jelly and spread it around the vial. The mercury was difficult to see.
I opened the vial (the petroleum jelly had countless tiny beads of mercury stuck in it) and placed it in another vial previously shown to have a good lid seal. Now the mercury is much easier to see. Here is a closeup of the bead. I plan to do nothing with the mercury in the near future except keep it with the element collection.