Nephrite as a surface treatment. A lot of nephrite tools and amulets are known since the Early Neolithic (VII mill. BC) to the Late Chalcolithic (V mill. BC) on the Balkans (mainly Bulgaria; also in Greece, Serbia, Croatia) from two or more unknown sources - Balkan "nephrite culture". Such tools are found in the Later Neolithic of Poland (from the most probable local source Jordanów), Sardinia (Italy) (unknown source) and Switzerland (Kostov, 2005; 2013). Single or just a few finds of nephrite artifacts are reported also from some other European countries. During Neolithic times, the key known sources of nephrite jade
Ornamental turning of ornamental turning and to restore, maintain and use the old equipment or, to adapt modern lathes for ornamental turning. Some are even bringing the hobby right up-to-date by building computer-controlled O.T. lathes. The accepted definitive published work on ornamental turning is the book "Turning and Mechanical Manipulation", by Charles and John Jacob Holtzapffel. Volume 5, entitled “The Principles and Practice of Ornamental or Complex Turning” is considered to be the "bible" of ornamental turning but there is much related information in the other volumes. Other useful books include: "Ornamental Turning", by J.H.Evans, "The Lathe & Its Uses", by J