They are not filled yet... Usually every item has sockets... gloves . armor , greaves , rings , necklaces etc etc ...
You can add to Armor,Weapons,Gloves,Boots,Helms some elemental stones(fire,wind,magic,earth,water) ... which in case of the armor they add elemental resist and in case of weapons elemental dmg ...
example... if u add a fire stone to a weapon u will get fire dmg(depends at the lvl of the stone) ... if u add a fire stone to an armor u will get fire resistance(depends at the lvl of the stone also) and etc etc .. . hope i helped
The stats are the green letters above the sockets ...