In fact thats the way they all are, by that I mean all the lids are priced higher than the skillets they go on.
Let me point out that what Perry is saying is a generalization. A good one, I agree, but there are some exceptions. The No. 5 block skillet with heat ring is worth a few buck more than a No. 5 high dome, smooth top cover. On the hammered set, the No. 8 skillet cover (PN 2098) also goes with the DO (PN 2008) and deep skillet/chicken fryer (PN 2028). I'd like one of the deep skillets for what the cover sells for. Can you think of any other exceptions?
There are a few cases where the cover and skillet are in the same ballpark, depending on the market and how bad the bidders on eBay want something. For example, I think it is not unreasonable to see a No. 10 slant Erie or a 10 block HR sell for more than either the high dome, smooth or the low, fully marked covers. Then there is the low, smooth No. 12 cover and the slant Erie skillet. Since these covers are pretty common, and with the high demand for clean, early skillets in the larger sizes, the prices are in the same ballpark.