does diamond gem attack power stack ?

[MielHoney]

hi, i wanna know if the diamond gem that give attack power stack togheter aka if i use 3 sparkling pentagonal diamond that give me 25 attack power each, will i get 75 more attack power or will it stay at 25 attack power,

lol... nevermind i just figure out that we can't stack gem of the same type lol =S