Velium Mastodon Fur Farming Location
Velium Mastodon Fur is used to create a Velium Mastodon Fur Cloak; a piece of gear that can help you reach 300 in Tailoring and that can also be used in the Crown of Deceit Quest which is added during Planes of Power. There's only a single enemy in the entire game that drops Velium Mastodon Fur and it can only be found in one zone.
If it wasn't already obvious by the pictures above, the enemy we're looking for is a glacier mastodon and these guys can be found roaming around Western Wastes, a zone that's on Velious. In order to reach Western Wastes you'll need a Druid or Wizard to port you to Cobalt Scar. Travel through Siren's Grotto and you'll find yourself at Western Wastes.
The glacier mastodons can be found roaming around all of Western Wastes except near the shore line and in the deep craters where you'll find raid con dragons. I have included a map below of all the different locations you'll want to hunt for the mastodons. Inside any of the blue circles is where you'll be most likely to find them.
In addition to hunting the glacier mastodons you'll also want to hunt Ice Burrowers for Ice Burrower Silk as well as Velium Hounds for Velium Hound Fur. Both of these items can also be used to raise Tailoring if you can't get enough Velium Mastodon Fur to do the job.
Velium Mastodon Fur Cloak (Trivial 322)
Once you collect all of the required ingredients to make the Velium Mastodon Fur Cloak you'll want to place them all into a Loom or Tailoring Kit and hit combine.
There is only a single item which you can make with Velium Mastodon Fur and that's a Velium Mastodon Cloak. This item has a few different purposes, one of them being the Crown of Deceit Quest that is added into the game during the Planes of Power expansion pack. The other thing is that this recipe counts towards 350 Tailoring.