Yes. My miner is GM, and when she puts the gloves on, she goes to 105 mining.
I'm going with the Stratics info here:
"When a miner reaches the minimum required mining skill and is mining a colored ore vein he has a 50% chance of actually digging up the colored ore.
Over all a miner digs the same amount of ore on all spots, he only gets more or less colored ore depending on his skill."
So, if it's colored ores you're after, the more mining skill, the better. My miner does fairly well in the colored/iron ratio, and if I were not convinced someone else already tested this, I'd go mining without the gloves.