On Halo 3 can you obtain all the skull achievments on co-op?

[chris]

Hey everyone, Last night I was playing Halo 3 with my sister on her Xbox, and we kept finding skulls that weren't triggering an achievment.

I was just wondering why this was happening?


NOTE: We were playing on Normal.

 

[spartan117]

if you already have them, you wont get the achievements again

 

[slayer420]

yeah...i did..and i got hayabusa helmet... gold skulls get achievements, silver skulls don't

 

[slayer420]

yeah...i did..and i got hayabusa helmet... gold skulls get achievements, silver skulls don't

 

[xx(Vantage)xx]

I don't think you can get it on normal, but co-op is the only way my brother and I got them...