I did some research on how Nepalese art and artists have influenced Tibetan culture. In the 13th century, objects of Nepalese art could be found in Tibet and even beyond in areas under the Chinese emperor. Nepalese artisans were dispatched to Lhasa at the request of Tibetan leaders to perform their workmanship and impart expert knowledge.
 
I have often visited the families of Nepali jewelers in Nepal who make Tibetan style jewelry in their home workshops.  These artisans are very skilled; the knowledge they have has been passed down from their forefathers.  The work of Newari artisans from the Kathmandu valley has been well-known for many centuries.  Newari artisans worked in Lhasa for many years and settled down there to live. Their craftsmanship became very popular, as they made jewelry and other art works to sell in the Tibetan marketplace.  Due to the unstable political situation in Tibet in the 1950s, most of the jewelry artisans had moved back to Kathmandu by 1960.   
 
The jewelers still use traditional techniques, working with just a few hand tools. Tree resin is used for gluing the stones.  Some special kinds of clay is the material that gives the pieces an antique finish.  To clean the jewelry they use a kind of tree fruit which acts as soap.  This is a very old method that originated when manufactured soap was not available.
 
Now, Newari artisans make prayer box pendants, statues of Buddhist deities, and other ritual objects in Lalitpur (a city of fine art in the Kathmandu valley).  Lalitpur was the original hometown of those Newari artisans who migrated to Tibet. A significant quantity of jewelry and ritual objects is still exported to Tibet and China from this city.
 
Tibetan beads and other Tibetan pendants are made at Bouddha, just outside Kathmandu. (Bouddhanath stupa or temple is one of the oldest Buddhist monuments in Nepal.) This is one of the places where Tibetan refugees settled after China took over Tibet. Nepalese artisans and Tibetan artisans work together and produce jewelry and other Tibetan handicrafts at Boudha.
 
Thamel, a neighborhood in Kathmandu, is another place where Tibetan style necklaces and other types of jewelry are hand-made by artisans. Here also the Tibetan and Nepalese artisans work side by side.  It is interesting to note that the style of workmanship is very different in the places mentioned above, because of the artisans varying backgrounds, ethnicity, and cultural traditions.
 
There are some Tibetan and Nepalese artists making jewelry who are living outside the Kathmandu valley, in towns such as Pokhara, Hetauda, and other smaller villages.  They have to travel  more than 12 hours to bring their jewelry to sell in Thamel.
 
It is very sad that some Nepali artisans have given up their craft and gone to the Gulf states in search of employment to support their families. It would be so much better for their families and for maintaining the artistic traditions of Nepal if the Nepali craftsmen could remain at home and make a good living by selling the products on the world market.