Some collectors want their coins slabbed. Ancient-coin collectors mostly don't. I have argued that slabs make it hard to see the coin--not because the coin cannot be clearly seen if you look at it, but because the slab distracts the mind. It is so much easier to see the large-type grade than it is to look at the coin itself. Sellers know that most of the value of a slabbed coin is in the grade, so they may fail to do much more than present the coin in its slab, without detailed identification. Look at this coin which came today which I cracked out of the slab (photo using an iPad). What do you think? Well, regardless of your final judgement, you at least have to look at the coin. I see a coin with substantial wear, but excellent depth of strike and centering. You might wish to know the ID, so I looked it up Maximian (MAXIMIANVS AVG) opposite four emperors sacrificing over tripod in from of the gate of a camp with towers, VICTORIAE SARMATICAE and ALE for Alexandria in exergue, B in field right. If you have RIC you can go to volume VI and find under Alexandria on page 661 that it is not listed, but the corresponding type is listed for Diocletian as Alexandria 8 ("c. 295") and "R4" (this coin would be 8b). The other types of argentei from this first issue at Alexandria are all R5 and the second issue has some "R4" with the VIRTVS MILITVM legend. So, now you know it is very (some would say "extremely") rare. Coupled with the pleasing appearance, that boosts the value a lot (to me). Now, with some more research you can find that any type of argenteus from Alexandria is relatively uncommon. The Sisak hoard had none. The Gemini auction VIII wrote "Tetrarchic argentei of Alexandria are very rare; for all emperors and all issues, Gautier in 1984 found in museum and private collections and in published catalogues only a total of 39 specimens." The major collection M&M XIII had none. Argentei have been found in the last decade, but catalogs where some were disbursed such as Freeman & Sear 11, 12, and 16 and Manhatten 3 had none from Alexandria. Nomos 3 had 3 from Alexandria, none of this type. acsearch yields about 53 from the search "argenteus Alexandria" but some are the same coin offered twice and none are of this type. So the coin might be "unique" and a seller would be justified in touting its rarity. But, it was slabbed. Can you forget all that above and look at what was offered and think how you would think with the following information? Here is what you see when a slab is offered: You see "Ch VF" which is pretty good but low grade for the high-grade-only collector. Look further and you see "Strike 5" (excellent) but "Surface 3, scratches" (not good). You do not see any significant ID. Neither my photo nor the seller's photo show much in the way of "scratches" (they are very hard to see in the interior of the camp). If you wanted FDC they would be a serious detraction from perfection, but for a "Ch VF" coin they are not much of a detraction. Personally, I like the surfaces with their toning. The people who bid against me were probably thinking "Only Ch VF and scratches--not good!" I am happy about that because I got it for about the price of a normal, common, argenteus. If you have a slabbed coin, or are thinking of buying a slabbed coin, I think the slab makes it hard to see the coin for what it really is. Tell us a story about a slabbed coin!