1 gram of Gold, various sized mesh (4,6,8,12,16 etc) for about $44 / gram.
You can add this gold to your own concentrates, sand, gravel, black sand blond sand, and know how much gold you should recover. This way you send $44 and you get $44 of gold. The best prices I have found for small gold nuggets, pickers, flakes, fines, is at GoldBay. So I'd start there.
We bought this #8 mesh for $44/gram ..... 8 Mesh Gold Nuggets
This way you are paying for gold and getting gold. You are also keeping your Shipping costs very low. Why pay for 5 lbs of dirt + the Shipping costs for 5 lbs of dirt and the US POST, Canada POST, Customs hassles with a huge bag of dirt in the mail when all you really want is some gold to practice panning ??? Anyway, just my 2 cents after panning pay dirt for a few years.