I hesitate to make any mention on the forum about this but I feel it may help someone else not make the stupid mistake I did.
I learned the hard way about shipping mercury, thought I would help someone out that needed some, well I am a packrat and a scrapper, and for years I collected mercury from switch's, and other items I parted out over the years, trying to be enviromentally friendly I just stored the mercury, never having any use for it, well to make a longer story short I shipped the mercury packing it and shipping in a way I thought was safe and ok, it was 17 pounds little over a cup, (I did not consider Liquid mercury expands with temperature)a dime size spill in a UPS center, ended up causing a havack, they shut down the plant called in Hazmat, air conditioning companies and so on, I had federal agents, DEQ, federal marshals and others come to my home and go through it with a fine tooth comb, I came close to going to prison, federal marshal were even on the forum at that time, you cannot believe the stress that caused, it was a long trying process, UPS sued me, the cost was $93,617.00, we almost lost our Home and property and everything my family has sweated and worked so hard for all our lives, I am afraid to mail a letter now.
mercury has no use in refining or in gold recovery in my opinion.
I can tell you from expierience before you ship anything find out the regulations from Authority's.
this hobby can cost you.