This one is super cool – there is a lot going on here. It is a doubly-terminated complete floater of scapolite, showing sharp and very distinct morphology, which is quite rare for scapolite. The crystal also demonstrates fascinating crystallization hollows which seem to evidence skeletal growth (also rare for scapolite).
The scapolite is either coated by a veneer of varying thickness, or partially replaced by orthoclase. There is only one chipped spot at one end which would help to confirm, and it’s hard to say – in that spot, there is a distinct layer of the orthoclase and then a distinct internal colourless scapolite without orthoclase. However, in other parts of this crystal, using strong backlighting, the internal translucency is mottled and this is more suggestive of partial pseudomorphism. Given that under strong light the translucency is quite good and based upon other specimens of this material that I have seen, I would characterize this specimen as internally mostly comprised of the original scapolite, with minor pseudomorphic replacement by orthoclase. Having said all of which, it is awesome sharp scapolite form!
In excellent condition – no damage except the one spot mentioned and I personally would stand it up with that spot underneath, so no issue. A great, interesting crystal!
Although all Sar-e-Sang scapolite group specimens tested have been shown to be marialite (as of the publication of T. Moore and R.Woodside’s excellent Mineralogical Record article on Sar-e-Sang, in April-May, 2014), and so it is quite likely that this is marialite, this specimen has not been tested, so I have used the group name “scapolite”.