The below Marcus Aurelius denarius is RIC 209. The coins is worn with significant scratches and graffiti on the reverse (X above the first numeral of XXIII so not to be confused with RIC 191!) amongst other things that put this arguably in the fine category. All good, I like it it with it's scars. I was curious what the cause of the lighter silvering or lack of patina in the specific areas of the reverse in the crevices around the chair was caused by? Marcus Aurelius laureate head right [M ANTONINVS AVG ARM PARTH MAX] with legend mostly worn TR P XXIII IMP V COS III Aequitas, draped, seated holding scales and cornucopia. Like a sneeze or cough my instant fear is that it has corona virus (or is fake) but the size and weight verify. Part of CNG Electronic Auction 479 October 21, 2020 As always thank you for the feedback. Please feel free to post a coin you find cool but has some scars.
My guess is lamination flaking, the black patinated layer flakes of either on its own or during cleaning and revealing the fresh silver layer. You can also see some flaking on his lips/mustache and some in front of his nose and forehead. Never try to scratch it, speaking from experience! These are my ‘scarred’ coins of Hadrian, Aurelius, and Nero, especially with Nero I tried to clean it but ended up only making the reverse more unsightly!
Believing in ruling out the easy answer first, I would check the light aresa with a toothpick to see if they could be wax residue from excessive polishing or preserving compounds. Just as today we have people who RenWax everything, there was a time that many people applied floor wax or whatever to improve the look of their coins. It it is wax, acetone might remove it but just picking locally might look better than a complete strip.
Below are the rest of that large lot from the El Medina collection. Like expensive booze high quality coins are wasted on me. I'm liking this Fine to Very Fine range that came with a nice assortment of virtues/deities and interesting features. If you think I have one wrong please let me know and if your thing is weathered coins enjoy the ride! Vespasian 69–79 A.D. Den RIC 772 laureate head right IMP CAESAR VESPASIANVS AVG PON MAX TR P COS VI Pax, naked to waist, seated left, holding branch extended in right hand, left hand in lap Really nice strike, some flan issues/clipping, nice patina with the dry espresso drops not withstanding Domitian 81–96 A.D. Den RIC 507 laureate head right IMP CAES DOMIT AVG GERM P M TR P VI IMP XIIII COS XIII CENS P P P Minerva standing right on capital of rostral column, holding spear and shield, owl at foot right Ex El Medina I Like this coin interesting patina and has that traditional feel of a roman coin, with the added impact of a serious scar on the face of the villain and an owl. Trajan 98–117 A.D. Den RIC 121 / RSC 81 laureate bust right, draped far shoulder (variant) IMP TRAIANO AVG GER DAC PM TRP COS V PP SPQR OPTIMO PRINC Felicitas standing left, holding caducius and cornucopiae This or Domitian/Minerva is my favorite coin of the lot with. Hadrian 117–138 A.D. Den RSC 920c laureate head right HADRIANVS AVGVSTVS LIBERALITAS AVG PP COS III Liberalitas standing right, emptying a cornucopia Ironic given world governments have been providing liberalitas and emptying the cornucopia. Struck between 129 and 130. Cleaned or polished beyond my preference but looks better in hand than my picture. Pius 138–161 A.D. Den RIC 313c AR laureate head right ANTONINVS AVG PIVS P P TR P XXIIII PIETATI AVG COS IIII Pietas, draped, standing left, holding child on each arm; at her sides, a child standing looking towards her and raising hand Pietas and Pius, so cool but for sure that reverse is worn and obverse polished (term?) Commodus 177–192 A.D. Den RIC III 159 A laureate head right M COMM ANT P FEL AVG BRIT PVBLIC FEL PM TR P XII IMP VIII COS V P P Felicitas standing left, holding patera and scepter Curious what good fortune this is meant to represent, struck 186-187. Gaul, Germany, Britain?