A treasure is a history. It says something about how it was collected and why. It's a good chance to bring in some of your campaigns history. Even if its just coins - and black dragons are notorious coin hoarders, in the horde of a dragon you should take the oppurtunity to have coins from earlier dynasties, kingdoms, and civilizations than the present. The older the dragon, the older the horde. A horde is not something easily described or tabulated. It should take at least a day of game time just to figure out what is in a horde.
I hate the 3rd edition method of generating treasure. I'm old school.
A dragon horde is at the least, not easy to cart off. And you will want want something like a cart. Actually, several cards.
A black dragon horde should have 1000's of coins regardless of denomination.
I would suggest something like:
400,000 copper peices
80,000 silver peices
2,000 exotic electrum peices
16,000 gold peices
500 exotic platinum peices
800 broken peices of colored glass (worthless)
500 assorted small semi-precious carbochons (avg. worth about 1 g.p.)
100 assorted large semi-precious carbochons (avg. worth about 10 g.p.)
50 assorted small gemstones (avg. worth about 50 g.p.)
120 tin plates (marginal value)
85 corroded brass ewers, plates, and cups (marginal value)
40 copper pots, many squashed and flattened (worth about 1 g.p. each)
3 iron caldrons (about 5 s.p. each)
1 large lead basin (about 5 s.p.)
5 silver plated platters (worth about 20 g.p. each)
18 small wooden shields (worthless)
10 small steel shields (half value)
6 large steel shields (half value)
3 tower shields (half value)
3 heavily rusted iron swords of an ancient mode (one is a cold iron sword +1 if the superficial rust is knocked away. The rest are worthless.)
15 steel swords in corroded scabbards (normal worth)
8 suits of rusted and torn chain mail (worthless)
15 suits of rusted scale mail, shedding scales (worthless)
1 battered suit of full plate (worthless)
160 simple peices of jewelry (copper, silver, and gold with glass, semiprecious and faux stones) such as might be worn by middle class ladies (worth about 3 g.p. each on average)
6 silver holy symbols of various dieties (worth 25 g.p. each)
12 ornate peices of jewelry with fine stones (worth about 500 g.p. on average, appraise 20+1d6 DC to tell the difference between the two. PC's without appraise skill should beware dishonest buyers.)
Rotten tapestries and banners, broken staffs, shattered bits of old chests, a broken wagon wheel, 18 human skulls (mustly crushed), many bits of bone
1 scroll case made from a bit of human femur with a wax seal, containing 5 tightly rolled and well preserved arcane spells of 1d6 level (Search DC 30, +10 DC if PC's only cart away things of obvious value)
2-5 magical items chosen as appropriate for your PC's class and needs with a total value of about 40,000 gp between them.
About half of the copper and silver peices should be corroded together into a mass at the bottom of the pile (weighing about 10 tons, and requiring significant effort to break into lumps and shovel into containers). A small portion of the other coins (say 10%) and gems should be littered in that pile.
