Yes,
MIR 1419i, known to Göbl in two specimens only. The plate coin is an
obverse die match to the one shown here. I disagree that it necessarily has to be gilded, the
flan shape is similar to other light
weight gold coins of that time, and does not appear to be that of an
antoninianus especially at 4- 8 o'clock. Gold is soft and with these very thin flans the edge often gets wavy in shape at that time, whereas the harder metal of an
antoninianus would just
crack - especially with a
flan of this size but only 2 g. Also, with most of these very thin gold issues with
radiate crown of the time, it is obvious that they were struck with regular
antoninianus dies, see f.e. the unique gold coin of
Aureolus, also many of Gallienus' and
Claudius II.
So without seing the coin in flesh and confirming the metal, I would be reluctant in condemning it right away.
Lars