For lapidary, the is kinda thin. You can research
on Idar Oberstein. They've been cutting stones there
since the 14th century. For historical documents, there's _The
Treatises of Benvenuto Cellini on Goldsmithing and Sculpture_ (ISBN
0-486-21568), written in the mid 1500's, The Pirotechnia (ISBN
0-486-26134), On Divers Arts (ISBN 0-486-23784) (which at the 11th
century predates the era you are looking at by a lot, but has a very
good description of the setup of a medieval workshop).
If you can find it, Medieval Craftsmen: Goldsmiths by John Cherry
(ISBN 0-8020-7711-0) has a lot of illustrations of jewelers shops
from the 1500s and 1600s.
There are a few more, but some of them are esoteric and kinda hard
to find. The stuff I listed above, and the bibliographies they
contain should get you further along than you are.
Ron Charlotte -- Gainesville, FL