Here i will tell you how to upgrade your weapons using Gems. This area of the game plagued me for weeks before I was able to figure it out. I wanted to create a section to help those that are in the same bind that I was. Keep in mind that the system holds true whether its a Gem, Ring, necklace, inherent bonus on blue majic armour, or any other form.
Magic damage- A broad catagory of damage. All damage is comprised of 2 main catagories; Magic and Physical damage. Magic damage is comprised of 5 subcatagories.
Element damage- The subcatagories of magic damage. The subcatagories are poison, curse, lightening, Fire, and ice. Spells often will tell you in the cheap 2Moons dil description if it deals this type of damage.
Physical damage- A broad catagory of damage. Auto attacks and skills can deal this type of damage. Spells often will tell you in the description if it deals this type of damage.