by Gene Wengert
firstname.lastname@example.org WOOD EXPLORER
Brazilian rosewood, also called jacaranda, is per- haps one of the most beau- tiful woods in the world.
However, extensive harvesting over
the past three centuries has virtually
eliminated this tree from the Brazilian
forests, so that today it is not supposed
to be harvested. The only material that
can be sold legally is old stock; such
material has to display a CITES Certificate, noting special approval. As might
be expected, the wood is extremely
The tree is classified as Dalbergia
nigra. Two other trees in this genus are
D. retusa, commonly called cocobolo,
and D. stevensonii, called Honduras
rosewood. In fact, Honduras rosewood, which is also a rare species, is
considered a substitute for Brazilian
rosewood; Honduras rosewood is
highly desired for making marimbas
and xylophones. Another substitute is
Santos rosewood (also called Santos
mahogany) which is classified as Mach-aerium scleroxcylon.
The Brazilian rosewood tree
sometimes attains a height of 125 feet,
and a diameter up to 4 feet; most trees
are smaller. Old defective stems yield
the most attractive wood grain and
color. Incidentally, the rosewood name
comes from a strong rose-like smell
when the lumber is sawn; the aroma
can sometimes be noted in the dried
lumber as well.
Rosewood has been used for
centuries in solid and veneer form for
beautiful furniture, pianos, parquet
flooring, instruments, tool and knife
handles, wood sculpture, carving and
turnery. Most recently, this wood was
prized for use in guitars due to its
extreme resonance and for producing
full tones, with deep basses and bril-
liant trebles. Guitar makers still revere
this wood. ;
Extensive harvesting has led to import restrictions.
; Want more? For more on this and other species, search the Wood Explorer collection at woodworkingnetwork.com
Density. The density of dried material ranges from 50 to 60 pounds per
cubic foot. A dry piece of lumber weighs
close to 5 pounds per board foot. It is so
heavy that it will barely float in water.
Drying. As with most high density
woods, drying is done slowly to prevent
checking. Shrinkage in drying is very
small...about 3. 6 percent.
Gluing and machining. Gluing is
not easy due to oils in the wood. Freshly
prepared surfaces are essential. Cleaning
the surfaces with a solvent is prudent. Its
high density also means that surfaces must
be exceptionally flat and true. Machining
requires very sharp tools.
Stability. Dried rosewood is extremely
stable, requiring a change of 6-1/2
percent MC to result in a 1 percent size
change tangentially (across the width
of flatsawn lumber). Radially (across
the width of quartersawn lumber), a 10
percent MC is required to result in a 1
percent size change.
Strength. As might be expected from
its density, rosewood is fairly strong
and stiff. The ultimate strength (MOR) is
19,000 psi. The stiffness (MOE) is 1. 88
million psi. The hardness is 2,720 pounds.
Color and grain. The sapwood is
white and is always considered waste.
The heartwood is various shades of
brown to chocolate or violet irregularly
and conspicuously streaked with black.