Cocobolo: Beautiful wood, surprisingly stable, but rare and expensive

Cocobolo or cocobola (Dalbergia retusa) is one of the most beautiful woods in the world. (Sometimes cocobolo is called Nicaragua rosewood. In Mexico, the wood is called granadillo.) The Dalbergia genus also includes Brazilian rosewood and Honduras rosewood, but cocobolo is heavier, stronger, and often considered more beautiful in appearance.

The cocobolo tree, found growing in Central America, including Costa Rica, Nicaragua, Panama, Mexico, Colombia, Salvador, Honduras, and Guatemala, is rather short (60 feet at most) and usually less than 24 inches in diameter. It requires at least 80 years to reach maturity. Being a legume, it can fix nitrogen in the soil, so it is an important tree in tropical areas where heavy rains tend to leach nutrients from the soil.

The primary use of this wood is in cutlery. Cocobolo wood makes beautiful handles with great color, natural water repellence, and high surface hardness. Another common use is for fine guitars. When the wood has a lot of grain figure, which is commonly found in veneers, it will be used as an accent wood for fine furniture.

The scarcity of this wood (slow growth; over-harvesting in the past; restricted harvesting in some countries — CITES Appendix III) and its beauty mean that prices are high. We cannot afford to use for more than accent woods.

Of major concern is that contact with the wood, especially the dust, can produce a reaction similar to poison ivy in many people. Apparently, the dust mixes with perspiration to create this reaction on the skin. Breathing problems also occur.

Processing suggestions and characteristics

Density. This wood has a density when kiln-dried over 1.0. In other words, it doesn’t float. When kiln-dried, it will weigh at least 70 pounds per cubic foot; a KD piece of lumber planed to 3/4” thickness will weigh over 4 pounds per BF.

Drying. Drying requires great care as the wood is prone to warping (especially when the grain is swirly or interlocked) and prone to face cracking or checking. Shrinkage in drying is reported to be under 4 percent, which is quite low.

Gluing and machining. The wood is quite waxy and so gluing is extremely difficult. Machining is moderately difficult, but the waxiness enhances final machining giving a wonderful smooth, polished surface.

Stability. This wood is amazingly stable. It requires a 7% moisture content change for a 1 percent size change tangentially and 10% change for a 1 percent size change radially.

Strength. There is no published strength data, but it certainly is stronger and stiffer than its close relative Brazilian rosewood. The values for Brazilian rosewood are ultimate strength (MOR) = 19,000 psi; stiffness (MOE) = 1.88 million psi; and hardness = 2720 pounds.

Color and grain. The heartwood color varies. After exposure to light, the wood turns dark red with some black stripping at times. The wood has natural luster. Some woods have rather straight grain, but others have very swirly grain patterns. Overall the surface grain is very smooth.

 

.

Have something to say? Share your thoughts with us in the comments below.

Profile picture for user genewengert
About the author
Gene Wengert

Gene Wengert, “The Wood Doctor” has been training people in efficient use of wood for 45 years. He is extension specialist emeritus at the University of Wisconsin-Madison.