nicking lead of school and church roofs is how i learned to melt down metal lol keywork search crucible on ebay and you will see a cone shaped ceramic object displayed approx 12 inches (30cm) long that will hold upto 1 kilo of molten metal, you place the unmelted metal inside, put it in a furness, or bonfire, let it melt, then using steel tongs of the blacksmith variety, not out the kitchen draw, you use them to pour the molten metal into the mold of your choosing and leave it to set.

there are 31.1 grams in a troy ounce, check the link i posted earlier, all the weights and conversions you will need are on that page you just need to scroll down and read, it also has the prices of gold at end of year dating back 100 years to present date also

edited by me to add,

if you are only doing small quantities, like a troy ounce at a time you could use a steel cone thats about 1cm thick that has both a lip on one side for easy pouring, and a heatproof fixed handle so that you can hold it over a open gas flame from your cooker, this does not work with electric hobs but you can use your kitch designer oven mits, in fact i recommend you do,

oh one more tip, dont ever put the cone on the kitchen sideboard when you have finished, not even for a second whilst hot, you'll be buying a new one, kitchen that is, when you have finished take it outside and bury it in a bucket of sand if you have pets to let it cool without causing any danger.

i will let you guess what is the best pet product to use has "mini" molds, perfect for small quantities

is leaving you guessing now........