And it is in the matter of gems that I ran straight in quicksand.
See, part of the problem is that in reality, most jewellers don't sell jewellery that is wildly valuable. Oh, sure, 'Tiffanys' exists somewhere, but most of the time the jeweller of a small town is going to make their money on selling trinkets to the masses, things made of copper, brass, pewter or bronze, with a bit of silver thrown in. Gold is very expensive, even white gold, so likely only a few pieces would exist, usually white gold, 14K or 18K. Platinum might turn up, but that might be just one or two pieces in the district.
That's no problem, but when determining which gems go into what items, the considerations start to produce a lot - and I mean a LOT - of individualized tables.
For example, if the jewellery item is a ring, it can only have a stone that is so large; a brass ring wouldn't have a precious stone set into it, and a gold ring wouldn't be set with an ornamental stone ... but excellent workmanship that's present in the former might mean a better setting while ordinary workmanship in the latter might mean that something like a citrine or a bloodstone wasn't out of place. If the piece is an earring, the stone can be much larger than the setting, since it can hang from a tiny bit of gold, so the balance of what kind of stone can be mixed with what kind of base metal is different. If the item is a necklace, it might have very little metal and a lot of gems, or it may have only a few gems set in lots of metal. Moreover, a necklace could be one string, or it could be ten strings, so there has to be an algorithm for determining the actual size of the item, which has to be a separate algorithm for determining the size of a tiara or a locket, since obviously the range on a necklace is far greater.
And all this is in relation to the trade tables themselves, which determine the type of gem or metal according to the part of the world one is in, so that turquoise would be common in jewelry here but rare over there, while over there pewter would be common but over there pewter would be non-existent. And so it goes. With all these different comparisons and random elements and circumstances and associations mixed together with the costs for lapidary and gemcutting and so on and so forth, I did reach a point last Tuesday where - after four days of fighting with it - I wanted to scream and stop trying. And since I was on vacation, I did.
I have not felt a need to pick it up since, so I may leave off the jeweller's table (and probably the lapidary's as well) for now and just move forward. At this point, that seems healthy. Then, when it no longer is holding up the posting of the grand table, I can get back to it and work at a half-rate version which can be steadily improved.
Look for me to get something up for the tables tomorrow or the day after.