I don't know if you can really say any are over or under valued. The values are based on what people are willing to pay.
Hate to say it cause I have over 30 of them, but right now I think the 1908-S IHC is overpriced in all circulated grades. Check the Jan '09 to the current Greysheet and you'll see a huge jump in prices, practically doubling in some grades and over 50% higher in most grades. Why??? Same as always, supply and demand probably. While I do think the prices were too low in Jan '09, they are now just crazy. Personally, I'd like to take some of the blame for it too. Since Nov '08 I've purchased over 50 of them in working on my grading set, around 40 in PCGS holders and another 10-20 or so raw. When I started I purchased every single PCGS graded 1908-S that I could find on eBay and on dealer websites. If it was available, I bought it... I pretty much did this for the next 3-4 months or so and prices kept going up. At the same time, I know another person was working on a 1908-S IHC grading set as well, buying everything he could find. Is one or two people enough to move a market that much??? probably not for an entire market, but probably enough for a single date/mm... For any coin, when one or more folks decide to hoard, prices eventually go up to a point where they become overvalued. Again, not sure if I and this other guy could really have that much of an effect, but until I hear a better answer, I think we may have.
the opposite is the 1844 dime, hundreds of these have shown up on Heritage in the last 6 months or so. http://coins.ha.com/common/search_r...=1844&Ntk=SI_Titles&N=51+793+794+791+1577+312 This is supposed to be a rare coin but they have ore than 20 on the block right now. That is more than they would offer in an entire decade in years past.
And as briefly discussed on my 7th post giveaway thread, i think one of the most undervalued coins right now is the 1909-O Barber Quarter. Barber collectors and those dealers who are aware of its rarity will ask for and get top dollar, but the price guides are way behind, especially the Greysheet. A few months ago an AU58 sold for $4025 at Heritage (Greysheet is around $500-$600 in AU I think). PCGS Guide has AU58 at under $1000!!!! Even in lower grades (if certified especially), this date trades at 3-5x sheet levels fairly often. I saw a VF20 (or may be VF25) go on eBay for $500+ So if you can find one of these in any grade at Greysheet levels BUY BUY BUY BUY!!!! (then sell to me for a quick 10% profit )
I think the Roosevelt series is under-valued!! I just don't think there is enough of us roosie lovers out there!!
As far as ancients go, I would be here all day naming undervalued things. But the most overvalued are, without a doubt: "Tribute pennies" of Tiberius, drachms and tetradrachms of Alexander the Great, and old-style Athenian tetradrachms.
