No idea why anyone would pay that much, though I will say that it looks like those coins might clean up quite nicely. Probably quite a few VF coins under those layers of dirt. I definitely see some nice detail there. But will it all add up to $300 when they are all cleaned up? Impossible to say. Its a gamble at that price.
Left-hand column, 4th down...anyone know that one? This same seller had lots that looked better to me that are going for 10-20% of this.
Perhaps all that 1st century AD stuff excited a few people? I mean, I don't remember the last time I saw an uncleaned lot that was mostly Augustus and Claudius (then again I don't really seek out lots like these). Even then, $300 seems pretty excessive if there aren't any rare types. First glance at the photos and I thought I was going to see a Placidia or something.
That is a common Claudius as of the Minerva type. It is very commonly found in England and certainly not a coin that could push that lot up to $300.
I see $300 here if they cleaned up with smooth surfaces but I am unable to predict that and don't see what makes it worth the risk. There are several Spanish mint coins in the group so there could be a special interest in that market. What is row 3 coin 3?
SPAIN, Carteia. Tyche / Poseidon https://www.acsearch.info/search.html?id=1123458 Must be at least uncommon; didn't find many although some could be buried in large mixed lots. Here's another, from CNG: 287, Lot: 18. Estimate $100. Sold for $60. This amount does not include the buyer’s fee. SPAIN, Carteia. After 44 BC. Æ Semis (21mm, 8.26 g, 9h). Turreted head of Fortuna right / Neptune standing left, holding dolphin and trident. ACIP 2615; RPC I 122. VF, rough earthen green patina.
I have one of those from a large mixed lot . For what it's worth, I don't think they're particularly desirable and don't see the one in the OP lot cleaning up to be worth more than the ~$30 examples on Vcoins: https://www.vcoins.com/en/Search.as...cords=100&SearchOnSale=False&Unassigned=False