"Mengu supreme Khan" with Mongke's tamgha with an "S-shaped" bar in the middle / "Zarb Bulgar" a slightly different Toluid Tamgha of Mongke. 15mm, 1.08 grams. Singatullina #8. 

The coins in the name of the Mongol Supreme Khan Mongke were struck by Khan Batu toward the end of his reign. These coins were virtually unknown until a few years ago.