Materia Cave >.<

I Finnaly got my golden chocobo, and have ventured to the 4th materia cave, (The inside has a yellow glow) But alas, there is no materia there. I’m guessing I have to be at a certian point in the game to trigger the materia, but just in case im missing something… can somone please explain? Thanks kindly. ^.^

Hey I played 7 over the summer cause I wanted to complete it before Advent Children. I completed 7 in 98 and tried to breed Chocobo’s but found it too hard and then I tried it again and I did it and the feeling of getting that gold chocobo was amazing and getting all the cool materia was amazing.

I’m trying to remember is it the cave their Wutai cause if it is then press the button where the yellow glow is I’m not sure but try it, I just can’t remember but it should be in there.

Could you specify where the said cave is? And, which materia do you get? I went into the caves about 3 years ago last time I played, and can’t remember which cave that is. You might have to be into Disc 3. I’m not sure.