How do you make the real expensive ones? I can do supernovium....
For supernovium put bars on a large display stand and then click the option which looks funny. 
You get compendium when you use 2, 3 or 4 different metal bars in your transmute. It will total all the values, add 25% and make a compendium bar worth that amount.
Example...
You use a Supernovium bar worth 5,000
add in 7 silver bars worth 500 total
5000+500 = 5,500 x 1.25 = 6,875 simolean valued Compendium bar.
While it starts out kind of slow, you are ahead by 875 simoleans on this transmute (6,875 value - 5,500 materials - 500 transmute cost = 875 profit) This amount will grow rapidly especially when you use higher value metals at the start. I like going to France and collecting Titaniums to use for my early combines to get the values accelerating quickly. There is also the smelting cost of $40 per ore / 320 per transmute, but that is a negligible cost. In the long run if you figure 1,000 per transmute in costs you can see it's really cheap and hardly worth mentioning once you get the process going.
Another way to make sure you have the cashflow to work this process... Transmute a collection of gems AND metals that total between 3500 and 4999 in value. You will get a uncut Tiberium as a result. Let that grow into a Spire Cut Tiberium and you will have about 30,000 - 40,000 as seed capital to transmute with.
http://www.carls-sims-3-guide.com/skills/collecting/worldadventures/transfiguration.phpAlso... the link above will take you to Carls guide on transmuting. It has a lot of good info regarding this. I have made suggestions on how to expand it slightly to cover the MIXED COMBINES like the gems + metals I mentioned above. Hopefully that will be incorporated soon.
