Roman Provincial Coins, a project of Oxford University's Ashmolean Museum. While RPC online lists tens of thousands of coins, the database is by no means complete. When I find a coin that's unlisted there or represented by a poorly-preserved example, I submit it for inclusion. That's what I did with this coin, which was not listed by RPC. When I first acquired it, I found it very hard to attribute and had to ask for help. Fortunately, @zumbly came to the rescue with his copy of Varbanov (who cites Karayotov), because there were no other examples anywhere online. Gordian AD 238-244 and Tranquillina. Roman provincial Æ 28.6 mm, 11.36 g, 7 h. Thrace, Mesembria, AD 241-244. Obv: ΑVΤ Κ Μ ΓΟΡΔΙΑΝΟC ΑVΓ CΕΒ-ΤΡΑΝΚVΛ|ΛΙΝΑ, laureate, draped and cuirassed bust of Gordian and draped bust of Tranquillina, wearing stephane, confronted. Rev: ΜΕCΑΜΒΡ-Ι-ΑΝΩΝ, Demeter standing left, wearing stephane, holding phiale and long torch. Refs: RPC VII.2, — (unassigned; ID 48421); Varbanov 4190, citing Karayatov 87; Corpus Nummorum 425 (citing Varbanov); SNG Copenhagen --; BMC --; Moushmov --; Lindgren --; Mionnet suppl 2 --; Sear --; Wiczay --. I submitted it to RPC last night and when I woke up, I received the following e-mail from Jerome Mairat: Dear RC, Many thanks for your recent feedback on RPC: it was very useful. It confirms the existence of the following type: https://rpc.ashmus.ox.ac.uk/type/48421 And your coin is used as the plate coin for this type. Best regards, Jerome The brand-new listing in RPC also includes the plate coin from the Shumen Museum in Bulgaria illustrated in Karayotov (no. 87, p. 408, pl. 136, pic. 87). It is, unsurprisingly, a double-die match to my coin. I also did the same thing for this previously unpublished coin. It took some help from fellow CT members and a bunch of online research in order to properly attribute it. I subsequently submitted my findings to RPC and it's now listed too. Faustina II, AD 147-175. Roman provincial Æ 5.84 g, 22.0 mm, 7 h. Bithynia-Pontus, Apamea. Obv: FAUST[INAC AUG], draped bust of Faustina II, right. Rev: UЄNU[S ... C]ICA dd, Venus seated right, head left, on dolphin swimming left, resting right arm on dolphin, uncertain object in left hand. Refs: RPC IV, 11815 (temporary); Waddington RG --; BMC --; Sear --; Mionnet Suppl 5 --; Lindgren --; Wiczay --. Notes: The exemplar of RPC IV 11815. Obverse die match to RPC IV.1 4729. So, I would encourage you to do the same. Post any coins you have submitted to an online database, such as RPC, Wildwinds, Corpus Nummorum, etc., and anything you feel is relevant, of course!