The choice between the different tree species varies according to :
1 - MANUFACTURING PROCESS : Cutting-off, unrolling, or saving.
Unrolling is obtained by the rotation of the ball, verging on the "pencil sharpener" system . This technique is above all used in industry (plywood, lathed,...)
<---- Example of burr of Chestnut on foot, Lozere source.
Burr of Elm before unrolling, Pyrenees source. ---->
Marc DAVY Documents.
In these two methods, the balls are previously plunged into a hot steam room . The veneers thus obtained may vary between 4 and 9 thenths of millimetre . In some cases, you get very decorative patterns.
Exemple of enrolled spotted mapletree
Sawing, which is the only old way, is not very used nowadays ; this is regrettable for us, since the tree species keep their warm original colour.
The veneers exceed 10 tenths of millimetre ; When you saw, you lose however some material ; and there is less drawing continuity from a sheet to another. Exemple of sawn veneers
2 - CUTTINGWAYS
If you go from the heart, to the outside of the ball, patterns are regular and lines are parallel : it's the "on stitch" or "on quarter" cutting-off.
If you go in the opposite direction, firstly in a tangential way, but still parallel to the diameter, you get much more drawings . This is the "on dosse" cutting-off.
3 - FLAWS IN WOOD
At the intersections of the tree branches or foot,
or when there are "cancers" (kind of balls) that prout on the trees, you may get nice burrs.
Veneers can also have some flaws : or example, if they have been affected by damp.
4 - THE OTHER MATERIALS USED IN MARQUETRY
See details concerning techniques and motives for the wood on: marquetry.org