The Heat Company are a manufacturer of excellent gloves and mitts, with a ton of smart features that make your life as an explorer easier. They originally designed their gloves for military and photography in the harshest conditions.
The staple of their product line is the HEAT Layer system, where you combine various liner gloves with mitts and overmitts. All parts of the System link together, and the mitts have loops for your wrists, so you can take any part on or off without worrying about losing them, even in strong winds. You can open the mitts if you need to operate more delicate gadgets or fiddle with small zips. The Heat Company also produce heat pads, which should be part of every 1st aid kit for cold adventures. All their gloves feature small pockets for the pads, which will keep your hands toasty warm for about 10h.
All their products are exceptionally well built, and they offer great support should you happen to have any issues. We recommend checking them out for any prolonged activity in cold places.