Increased elemental damage vs increased fire damage on ruby jewels

Hi, I am trying to figure out how to scale my gas grenade explosion damage on my witch hunter. When looking for the affixes on different jewels, I got puzzled by the prefixes "X% increased fire damage" and "X% increased elemental damage" both of which can role on ruby jewels. Does the latter scale my explode damage the same way increased fire damage does or am I missing something? Would a ruby jewel with both modifiers be something I should be looking for?
Any explanation would be highly appreciated.

Bump. I'm curious about this as well.

Bump. Hoping for some clarification, if anyone has done testing on this.

I mean I havent researched it but for most things there are multiple things that can scale abilities or damage this being one of those cases.

If you get increased elemental damage you gain increased cold damage, increased lightning damage and increased fire damage. This would be more noticeable if you had some kind of conversion build that converted the damage types or used multiple. But you would still be gaining that stat you are looking for. You could even get both of them if you wanted

Basically, they do the same. The fire one may have higher accessible numbers though since it only affects one of the elements

elemental damage is basically three mods in one

increased fire damage
increased cold damage
increased lightning damage

if you have only fire damage, inc elemental damage and inc fire damage are the same thing. the value of this mod greatly depends on your gear and tree though, since it's additive

I got a ring that increased fire damage by 30%, however after messing around with it for a while, it felt like it was not working. Gas Grenade explosion has damage listed out with a physical part and a fire part, but the paper dps for the fire did not change with the ring equipped. I was rotating it with a ring that added fire damage to attacks, and that did adjust the paper dps section for Fire damage.