The Quaternary succession of the Bulè and Alpetto valleys (Monviso Massif, Piedmont) as a possible supply for prehistoric jade axes raw material

[object Object]This contribution presents a geological mapping
of the Quaternary succession of the Bule` and low
Alpetto tributary valleys (Po Valley, Piedmont), together
with preliminary data on its petrography. The investigated
area, covering an altitude range between 3015 and 1485 m
a.s.l., is located in the Monviso Massif Ophiolite Complex,
at the contact with marble and calcschist of the Dora-Maira
Massif cover. The Quaternary sequence mainly consists of
glacial, outwash, debris and landslide deposits, with local
torrential/avalanche and colluvial bodies. The investigation
on the petrographic composition of these sediments has
allowed to recognize the occasional occurrence of jadeitite
boulders, likely exploited during the Neolithic period for
axe head production. Four possible jadeitite blocks have
been found; one of them is described here for the first time,
sizing up to 1 m3. In detail, one of the finds is a Neolithic
site of jade polishing in the high Bule` Valley that was
referred to the middle of V millennium BC (Allisio, La
Preistoria e l'alta Valle Po, Lar Editore, Perosa Argentina,
2012). The jadeitite blocks have been found in the debris
(site A), landslide (site B), glacial (site C) and outwash
(site D) sediments. The petrographic characterization of the
new jadeitite samples might potentially shed light on the
still controversial genesis of these peculiar rocks.