My theory on these shapes is that the metal was rolled out in long strips, then a circular punch was used to cut off individual flans. Occasionally the width of the strip was less than the diameter of the punch, hence the odd shape. Something like this perhaps...
Oval: Square: Rectangle: *Does anyone know if ancients made any coins with triangle shapes? If I can get that then I'll have all the basic shapes complete, as I also have round coins which I didn't mention here as this is a "less than round" thread.
Tooth from Akragas Squashed overstrike from Apollonia Pontica Nugget from Aegina Oval from Athens Oval from Arados Square Widow's Mite Two handled Widow's Mite Byzantine overstrike of 1/4 of earlier round coin
@dougsmit love that Oval from Athens. Is it an early issue? fraction? Athena looks much less feminine than usual.
My favourite spectacular failure to be round is this follis of Theodosius III of Adramytium, 715-717. My rarest piece of absolute junk.
Commodus Coin: Bronze Dupondis M COMMODVS ANT P FELIX AVG BRIT - Laureate head right MINER VIC (...) TR P VIII COS V DES VI S-C - Minerva standing left, holding Victory and reversed spear; shield leaning before against her leg; trophy behind Mint: Rome? (177-192 AD) Wt./Size/Axis: 20.54g / 29mm / - References: RIC III 546 (Dupondius) cf. MIR 18 786-6/27 (Securitas) Cohen 372.
Aigina, Aegina Coin: Silver Stater None - Land tortoise viewed from above None - Geometric incuse skew pattern with 5 segments Mint: Aegina (456-431BC) Wt./Size/Axis: 11.89g / 22mm / - References: Similar to SNGCop 516 Similar to Dewing 1683 Similar to BMC 146