Internet resources for Greek and Roman coins
Below are a few sites that have useful information about ancient coins, or at least good pictures of them. There are hundreds, if not thousands of web sites dealing with ancient coins, but few have any scholarly value. In general printed handbooks remain a far better introduction than anything available on the internet.
A lot of internet resources are compiled by and for collectors and reflect their interests, particularly the pursuit of rare or unpublished types, which they can check against published lists of coins. As a result many of these sites are not particularly interesting for anyone other than the enthusiast collector, and are designed to advise people about the hobby of collecting ancient coins and/or to show off personal collections. Others are maintained by dealers; these often have plenty of photographs but not much information and again they focus on the interests of collectors and investors. Many of these sites provide lists of coins, with illustrations, but without any useful accompanying information.
One of the better examples of this kind of site is Doug Smith’s Ancients Page. This contains general information about identification and a number of quirky but often quite interesting and well-informed essays on various numismatic topics. A similar kind of resource is maintained by Warren Esty. You might also find something of interest at these sites.
Images and identification
A general guide to identifying Roman coins, particularly those found in Britain, is maintained by the Portable Antiquities Scheme.
A good search engine for images of ancient coins illustrates expensive coins sold at auctions. While this is an excellent resource for obtaining images of many kinds of ancient coinage, common coins are not so common on this site. A long list of ancient coins, with illustrations, is to be found at Wild Winds. A listing of Greek coins, based around the now rather outdated Historia Numorum, is the Digital Historia Numorum. Unlike many of the other sites, this provides some background information about mints and issues, rather than providing just a bare list of coins. There are various sites dedicated to regions or single mints, for example for Ephesus and Miletus. Many Roman coins from the Republic to the Empire are to be found in the Virtual Catalog of Roman Coins; cf. another site relating to Roman coins. Sites are available for the identification of common Late Roman bronzes; and with some details about Roman provincial coinage.