I’ve been sitting on this one for a while too … mostly because of disorganization. In any event, from IC Russia:
Ruins of the burnt down palace of the ancient king Mithradates VI Eupator have been discovered in Taman Peninsula, on the place of the old city of Phanagoria.
On the site of fire archeologists also found purses with coins, and broken but otherwise well-preserved earthenware.
“The found coins are not a hoard: they were abandoned by the king”s family and courtiers trying to escape from the fire and violence” – the head of the Taman expedition Vladimir Kuznetsov says.
He reminded that Phanagoria, once a Greek colonial settlement, was for several centuries the capital of the Asian part of the Bosporus state. As for Mithradates VI, he lived there about the year 63 BC. Historians assume that a rebellion broke up in the city, and the residents captured the king”s daughter and four sons, and set on fire the centre of the city, including the palace, where the king”s family lived.
The account of the destruction of the palace is in Appian 108 (courtesy of Livius.org):
When he had recovered from his illness and his army was collected (it consisted of sixty picked cohorts of 6,000 men each and a great multitude of other troops, besides ships and strongholds that had been captured by his generals while he was sick) he sent a part of it across the strait to Phanagoria, another trading place at the mouth of the sea, in order to possess himself of the passage on either side while Pompey was still in Syria.
Castor of Phanagoria, who had once been maltreated by Trypho, the king’s eunuch, fell upon the latter as he was entering the town, killed him, and summoned the citizens to revolt. Although the citadel was already held by Artaphernes and other sons of Mithridates, the inhabitants piled wood around it and set it on fire, in consequence of which Artaphernes, Darius, Xerxes, and Oxathres, sons, and Eupatra, a daughter, of Mithridates, in fear of the fire, surrendered themselves and were led into captivity. Of these Artaphernes alone was about forty years of age; the others were handsome children.
Tip o’ the pileus to Adrienne Mayor who pointed me in the direction of a photo of one of the coins:

… Clearly a coin of Mithridates VI Eupator … There’s also a news video (in Russian) here (and some more photos if you can figure out the tabs) …