The "gold chloride" from Mallinckrodt was probably supplied (quite a while ago from the looks of it) as a chemical laboratory reagent or possibly to use in a plating bath. From its appearance, it is probably actually the monohydrate (AuCl3.H2O) with a gold content of about 197/331 = 60%, approximately. It is supplied in an ampoule for protect it from moisture in the atmosphere otherwise it would soon end up as a gooey mess since it quite readily absorbs moisture. I am not sure whether it has any particular value over and above its gold content plus the cost of preparing it from gold and then sealing it in a nice ampoule. It has a close relationship with the stuff you get from gold + aqua regia. That product is AuCl3 + HCl or HAuCl4. If you want to recover the gold, break the ampoule, dissolve the contents in some appropriate volume of water and proceed in the same way as you would if you had dissolved some gold in aqua regia and then neutralised the excess acids.
This ampule is part of the dust bin of medical quackery from 1940s,50s this was injected as a cure or to help the symptoms of severe rhmatoid arthritis.Is worth more as a medicinal antique.
My father had severe Rheumatoid Arthritis and I remember him going to Toledo, OH for gold treatments as recently as 20 years ago. The only treatment that was successful for him was replacing joints with plastic and pain medication.
Sorry to resurrect an ancient post but gold chloride in these ampules were used by photographers (like myself) to make toners for B&W prints. Nelson Gold Toner is a classic example of one of these toners as well as toner formulae for really old print processes like albumen and Printing Out Paper. With this 1 gram tube I would make 100mls of 1% solution for use in different formulas.