FMF - Friends of Minerals Forum, discussion and message board

[vic rzonca]

I'm posting some closeups of the unknown I'm trying to identify. Maybe they may help in the image only identification.

[Carl]

Regarding the white mineral, hard to tell from just pictures, but I have seen stilbite that has been altered by weathering look like this in Virginia trap rock quarries.

[Gagat Minerals]

I'm generally of the position, that we should not even try to identify 'zeolites' in such forms. "This could be" .... - my first impression from very 'fresh' (on the beginning of dehydration process) laumontite till stilbite but this is only guessing. Thanks for the heulandite picture, as far as from New Jersey I know many specimens, but Massachusetts is for me 'terra incognita'.

[Tobi]

Like Carl, I think the unknown white material could be stilbite ...
(At least it reminds me of the sheaf-like structure that stilbite often has.)