« Jade News - Fall 2003 | Main | High-pressure, metasomatic rocks along the Motagua Fault Zone, Guatemala »
Wednesday
Apr302003

Jade in Switzerland - April 2003

A visit to two sites with Ann and Russell Beck

by Herbert Giess Switzerland Spring 2003



1.0 Introduction
In the Bulletin of the Friends of Jade, Volume VIII and published in summer 1994, I had the opportunity to report on the use of Nephrite for Neolithic tools as also on the search of in-situ Nephrite in the Swiss Alps. In April this year I have been pleased, 10 years after my first visit, to show to Russell Beck, the eminent Jade specialist from New Zealand, the Swiss Nephrite sites of Val Faller and of Scortaseo/Poschiavo. The following lines are intended to give you information on the actual status of the sites and, with the help of the now ubiquitous digital cameras and inkjet printing, also some views how the site changed over the years.

2.0 The sites in Val Faller
These sites have been described in the Bulletin of Friends of Jade on page 24 and are the locations where Mr. Otto Welter of Bonn/Germany discovered, in the summer of 1910, the first time in-situ Nephrite in Switzerland. These most accessible sites are located in the Oberhalbstein Ophiolite area at the entrance of a valley called Val Faller. This is a small narrow valley, at about 1480m of elevation, which branches off westward, at Muhlen/Mulegns, from the main north-south road which leads from Tiefencastel, over the Julier Pass, to St. Moritz.


Swiss Map “Bivio” at 1:15.000 scale and road signs at the start of the Val Faller in Mulegns

O. Welter, after having explored the Oberhalbstein area the two years before and finding several isolated Nephrite boulders near Salux, a village not far from Mulegns, described the sites as follows: ... the first Nephrite is visible on left part of the valley opposite the 5 th telephone line pole and a little remaining material is located next to the 6 th pole. The main quantity is to be found fifty paces after the first road bend close to the road. Already from far away the whitish Nephrite catches the eye and cannot be missed.

I have visited the site in 1993 in preparation of my FOJ contribution and the on April 13 th 2003 with Russell Beck and his wife Ann.

The Nephrite found at these sites is very schistose and associated with nearby Serpentine.


O. Welters “Telephone pole” Nephrite site on the road into Val Faller looking toward Mulegns on the left image. Picture taken in summer 1993

The above outcrop has been recently conveniently sectioned during road enlargement work and Russell Beck was able to read the local geological features like an open book. The outcrop is in contact with Serpentine and formed from variegated rock containing bands of white Tremolite, red and greenish Schist and sections where felted Nephrite was present.

Same view of the outcrop as found in April 2003 with the now conveniently placed fresh trans-section closely inspected by Russell and Ann Beck.


Fresh surface of the Nephrite rock-bearing outcrop with white Tremolite fiber bundles (mountain leather) picked out by Russell on the left and a close up of them intermingled with green and purple Schist.

O.Welter illustrated the 3 rd deposit in Val Faller in his publication “ Ein Beitrag zur Geologie des Nephrits in den Alpen und im Frankenwalde” published in “Neues Jahrbuch fur Mineralogie, Geologie und Palaontologie Vol. 2, 1 st Fascicule” in 1911, with a drawing based on a picture taken by Mr. Bancroft of Montreal/Canada which accompanied him to the site.


Sketch in O.Welter’s paper showing the Nephrite rock outcrop on the road bend into Val Faller located between Serpentine and Spilite. The outline of a person (Mr. Welter?) at the arrow gives the size of the outcrop.

As already reported in the Bulletin, the mayor part of the Nephrite outcrop has been removed during a road enlargement in 1972 and only leftover patches of white weathered Nephrite are visible under the grass and trees.


The 3 rd Nephrite site in Val Faller in summer 1993, summer 1910 and in April 2003. Note the still original iron road barrier poles dating at least from 1910.





White weathered Nephrite at the 3 rd site in 1993 and in 2003

Russell Beck has inspected with great interest the white outcrops and after a few energetic blows with the hammer into the soft white surface material, he quickly hit though and resonant Nephrite. Again Serpentine was just few paces away. The material showed a weakly felted fibrous structure with a lot of schistosity quite far from the New Zealand Pounamu Jade he is normally using for his well known carvings but Nephrite or Jade was it nevertheless!


Weathered white Nephrite and a chunk of more solid one


A 40mm long sliver of schistose greenish Val Faller Nephrite from site 3.

3.0 The site in Scortaseo/Poschiavo


The Scortaseao site is the place in Switzerland where the largest volume of Nephrite is found. The Nephrite of this site has a particular pea like structure and has been described in detail by Dietrich/Quervain in Volume 46 of the “Geotechnische Serie Switzerland” in 1965 and by myself starting on page 37 of the Bulletin of 1994.

Russell was naturally very keen to visit also this site, located approximately 40Km south from the Val Faller site and near the very end of the Oberhalbstein Serpentine horizon.


Russell Beck checking, from the 2328m Bernina Pass, the road down into the Poschiavo valley

The Scortaseo Nephrite is however not in contact with Serpentine but associated with Talcum and Dolomitic Marble.

During my first visit in 1993, the Nephrite blocs, leftover from the Talcum extraction, were plentiful and formed large taluses.

Reaching the site in April this year, through the last remnants of snow, we discovered that the site had quite changed and rock crushing equipment was installed.


Reaching the site in April 2003 and discovering the rock crusher

We learned that the nearby town of La Prese/Poschiavo had decided to remove all loose material, Nephrite or not, and transform it into road paving material! We scampered over the site and have been able to find some remaining boulders with the characteristic pea size Nephrite agglomerates.


Talus of discarded Nephrite blocs in summer 1993 just below the Dolomitic Marble and Talcum cliffs in Scortaseo


Russell Beck inspecting a remaining large Scortaseo Nephrite boulder with the 4-8mm small sized Nephrite globules (on the right) showing the reddish surface alteration.


Boulder with weathered outer surface showing brownish stained Nephrite peas in the white Calcite matrix


Trying to get out, unsuccessfully, a buried treasure and Nephrite peas on a boulder surface.


Quite soon the Scortaseo Jade will be gone as crushed paving material via this conveyor belt! The Vartegna Crest rising to 3000m behind the V-shaped scar of the Scortaseo Talcum/Jade mine.

PrintView Printer Friendly Version

EmailEmail Article to Friend

Reader Comments (2)

Hi Herbert.

How would you rate this nephrite on a scale of 1 to 10? Is this still a good place to go rock hounding? What colors of jade do you find there?

Thanks!

Mark Mendoza
December 2, 2006 | Registered CommenterJade Hunter
'Tis a shame the nephrite was being crushed for common road gravel. I've only recently learned of Swiss jade and I thought it had been completely mined out many years ago- even Neolithic Man had an appreciation for the material! Is there a chance one can still go and collect decent samples?
Keep up the good work - even if it is far away from California.
Thanks, Michael
August 7, 2009 | Unregistered CommenterMichael C. Smith

PostPost a New Comment

Enter your information below to add a new comment.
Author Email (optional):
Author URL (optional):
Post:
 
All HTML will be escaped. Hyperlinks will be created for URLs automatically.