We don't have any belongings and even if we did, it is very difficult if not impossible to trace them specifically to the prophet. Moreover, what purpose would such a study accomplish? Nothing.
Salaam,
My "blessed" ancestors may have done a little of "religion building" themselves.
The implications, opportunities to learn are endless. It should expose the lies at least.
http//www.turkishembassy.org/traveltourism/sacredrelics.htm
Some photos, not very good I am afraid with statements of questionable monotheism
http//www.dinvekitap.com/Kutsal_Emanetler/Kutsal_Emanetler.asp
You can make out a strain of hair in the centre
http//www.geocities.com/hicaz2001/sakaliserif4.jpg