 Cocobolo (Dalbergia retusa)
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Common Name(s): Cocobolo, Cocobola
Scientific Name: Dalbergia retusa Distribution: Central America Tree Size: 45-60 ft (14-18 m) tall, 1.5-2 ft (50-60 cm) trunk diameter Average Dried Weight: 69 lbs/ft3 (1,095 kg/m3) Specific Gravity (Basic, 12% MC): .89, 1.10 Janka Hardness: 2,960 lbf (14,140 N) Modulus of Rupture: No data available: most likely in excess of 18,970 lbf/in2 (130.8 MPa), the values for Brazilian Rosewood (Dalbergia nigra) Elastic Modulus: No data available: most likely in excess of 2,100,000 lbf/in2 (14.48 GPa), the values for Brazilian Rosewood (Dalbergia nigra) Crushing Strength: No data available: most likely in excess of 9,600 lbf/in2 (66.2 MPa), the values for Brazilian Rosewood (Dalbergia nigra) Shrinkage: Radial: 2.7%, Tangential: 4.3%, Volumetric: 7.0%, T/R Ratio: 1.6 |
Color/Appearance: Cocobolo can be seen in a kaleidoscope of different colors, ranging from yellow, orange, red, and shades of brown with streaks of black or purple. Sapwood is typically a very pale yellow. Colors are lighter when freshly sanded/cut, and darken with age; for more information, see the article on preventing color changes in exotic woods.
Grain/Texture: Grain is straight to interlocked, with a fine even texture. Good natural luster.
Endgrain: Diffuse-porous; medium to very large pores in no specific arrangement, very few; solitary and radial multiples of 2-3; various mineral deposits occasionally present; parenchyma diffuse-in-aggregates, vasicentric, and marginal; rays narrow, fairly close spacing.
Rot Resistance: Rated as very durable, and also resistant to insect attack. Its natural oils are reported to give it good resistance to degrade from wet/dry cycles.
Workability: Due to the high oil content found in this wood, it can occasionally cause problems with gluing. Also, the wood’s color can bleed into surrounding wood when applying a finish, so care must be taken on the initial seal coats not to smear the wood’s color/oils into surrounding areas. Tearout can occur during planing if interlocked grain is present; the wood also has a moderate blunting effect on cutting edges/tools due to its high density. Cocobolo has excellent turning properties.
Odor: Cocobolo has a distinct spice-like scent when being worked, which some find unpleasant: though it has been used in at least one women’s perfume.
Allergies/Toxicity: Notoriously allergenic. Reported as a sensitizer; can cause skin, eye, and respiratory irritation, as well as nausea, pink-eye, and asthma-like symptoms. See the articles Wood Allergies and Toxicity and Wood Dust Safety for more information.
Pricing/Availability: Cocobolo is in limited supply, (proposals have been made—as of yet unsuccessfully—to add Cocobolo as an endangered species in the CITES Appendix II), and is also in relatively high demand, (for ornamental purposes), and is likely to be quite expensive. Prices should compare similarly to other rosewoods in the Dalbergia genus.
Sustainability: This wood species is in CITES Appendix III (wood from Guatemala and Panama only), and is on the IUCN Red List. It is listed as vulnerable due to a population reduction of over 20% in the past three generations, caused by a decline in its natural range, and exploitation.
Common Uses: Fine furniture, musical instruments, turnings, and other small specialty objects.
Comments: One of today’s most prized lumbers for its outstanding color and figure; yet also one of the most infamous for its difficulty in gluing, and its tendency to cause allergic reactions in woodworkers.
Also, there are a few misleading reports of Cocobolo’s Janka hardness being only about 1,100 lbf, and it’s modulus of elasticity at only about 1,100,000 lbf/in2: which is almost certainly either a typo or a different wood than what is commonly called Cocobolo (Dalbergia retusa). Reports indicate that Cocobolo is stronger and denser than Brazilian Rosewood, and that is the basis for the strength values (bending strength and modulus of elasticity) that are quoted at the top of this page.
Specific gravity is used to predict the hardness of wood with a fair degree of accuracy, and given its incredibly high density, (it sinks in water: see video below), Cocobolo’s hardness (and other strength properties) is most likely several times higher than the 1,100 lbf which is sometimes reported.
- African Blackwood (Dalbergia melanoxylon)
- Amazon Rosewood (Dalbergia spruceana)
- Bois de Rose (Dalbergia maritima)
- Brazilian Rosewood (Dalbergia nigra)
- Burmese Blackwood (Dalbergia cultrata)
- Burmese Rosewood (Dalbergia oliveri)
- East Indian Rosewood (Dalbergia latifolia)
- Honduran Rosewood (Dalbergia stevensonii)
- Kingwood (Dalbergia cearensis)
- Madagascar Rosewood (Dalbergia baronii)
- Sissoo (Dalbergia sissoo)
- Tulipwood (Dalbergia decipularis)
- Yucatan Rosewood (Dalbergia yucatensis)
Scans/Pictures: Below you can see a small representation of the wide array of colors that can be seen in Cocobolo. Also, due to it’s high density (over 1000 kg/m3) you can also view a video of Cocobolo showing how it sinks in water. A special thanks to Steve Earis for providing the turned photo of this wood species.
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Cocobolo (sanded) |
 Cocobolo (sealed) |
 Cocobolo (endgrain) |
 Cocobolo (endgrain 10x) |
 Cocobolo (turned) |
 Cocobolo (kaleidoscopic colors) |
March 26th, 2011 at 4:16 pm
I made some handles for kitchen knives from cocobolo back about 1970. No finish of any kind was placed on them. They are fine today in spite of almost daily use and daily washing. One of them shows a slight crack, however.
January 10th, 2012 at 7:34 pm
Specific gravity wrong. Must be greater than 1 to sink in water.
May 17th, 2012 at 10:52 am
@ Jim: Specific gravity is definitely wrong.
If you look at the average dried weight: 1,070 kg/m3, converting to units of g per cubic cm gives you a specific gravity of 1.07, which would sink in water.
September 8th, 2012 at 9:13 pm
Hi,do you think that BASIC Specific Gravity = Specific Gravity?,and
that Specific Gravity = Weight?or if the green lumber = dried lumber?please let me know what happen?.Some literature say Cocobolo Specific Gravity is 1.1 for that sinks in water.
September 10th, 2012 at 11:21 am
Regarding all the comments on specific gravity listed above:
If you click on the link for Basic Specific Gravity at the top of the page, you’ll realize that BASIC SG is not the same as Specific gravity. (One of these days I’m going to write an article explaining how misused and useless specific gravity numbers are without a moisture content!) Anyhow, if you follow the link, you’ll get the following explanation:
Typically it is based upon a wood’s oven-dry weight, (meaning a moisture content of 0%, which is the lightest the wood can ever get), and its green volume, that is, when it is freshly cut: having the largest possible volume. This may seem like a double-standard—to calculate this density from the wood’s dry weight, and its green volume—but this standardization, commonly called the “basic specific gravity,” prevents any irregularities or inconsistencies from occurring, mainly because it uses predictable extremes (i.e., lightest weight and largest volume) to calculate the SG value.
Using a wood’s basic specific gravity, along with its volumetric shrinkage data, the average dried weight can be calculated at a number of moisture contents, ranging from 0% up to 30%.
September 23rd, 2012 at 7:58 pm
I made an entire side table out of Cocobolo. The only part of the table that is not Cocobolo is the drawer box, which is naturally-stained soft maple which gives the Cocobolo a very nice contrast.
October 3rd, 2012 at 10:14 pm
I do simple turning, just reel seats and pens, but I do a lot of it, and early on I wasn’t as careful about dust as I should have been. Cocobolo was my favorite wood, and I turned a lot of it. Sadly, I am now allergic to it. As far as my body is concerned, it might as well be radioactive dust! And I am not a person prone to allergies, as far as I know my allergy to Cocobolo is it, although that sensitivity has made me be very careful around any wood in the Dalbergia family. This is a shame since that family contains some of the most beautiful woods in the world. I read somewhere on the web that “there are two types of wood turners, those who are allergic to Cocobolo, and those who will be! So be warned, take every precaution you can when working with this beautiful wood to avoid contact with its dust! It might not bother you now, but it will if you aren’t careful.
October 4th, 2012 at 10:10 pm
Dear Tom,
Actually, Cocobolo saw dust is extremely dangerous in certain cases. Irritation at the sites where dust contacted has been reported in some cases, but when sanding, take every precautionary you can, especially wearing a dust mask. I had a first hand experience with router dust and finish sander dust. When fine-sanding, the moment the dust particles enter your lungs, the fluid in your lungs causes a chemical reaction that turns the fine dust into a very potent acid and can be very lethal. i personally breathed some in when working on a table made of Cocobolo, wasn’t aware of the dangers, breathed in some of the dust and missed three entire weeks of school because of it. the dust only got into my tracheae and caused pretty bad burns, but I was extremely fortunate and lucky. I must agree with your comment that the Dalbergia family of woods is some of the most beautiful and extravagant wood out there. Best of luck with turning!
~Tanner~
October 4th, 2012 at 11:06 pm
Well, the precaution I have taken is to simply no longer work with Cocobolo. When I was working with it I didn’t experience respiratory problems, but the skin reactions were so severe (redness that felt like sunburn, itching that might last for a week, even blistering)that it simply wasn’t worth it. Add to that my wife’s “Are you CRAZY!” whenever I dream up some new scheme that might let me turn it again! The odds are simply stacked against Cocobolo (but I still haven’t managed to part with the wood I have on hand).
October 4th, 2012 at 11:37 pm
well sometimes compromise must be made. And also, Cocobolo is getting very hard to find now-a-days, so not being able to work with it might not be as bad! I encourage to try to find a new way to turn it once again without getting the painful side effects. best of luck!
~Tanner~
March 18th, 2013 at 10:02 am
I am not allergic to cocobolo but one day when was making a pen from it i began to experience an awful burning sensation in both nostrils and my eyes began to water. Am i allergic to this wood? P.S. I have worked with cocobolo twice, in a well ventilated shop.
March 18th, 2013 at 4:31 pm
When any fine particles of Cocobolo hit a mucus gland, it turns into a fine acid, due to the fact of the type of oil in the wood. So when it hits your nose the fine or semi-fine particles turn into a mild acid. In the most severe cases, very fine particles from sanding that make it into your lungs produce nitric acid in your lungs, which is very lethal. I was once routing mortises into a leg made of Cocobolo and had a bunch of rough dust fly up my nose and experienced the same thing you experienced. Of course, the acid production ratio is different for every person because of % body fat, metabolism, etc. etc. Hope this sheds some light on the topic of this most beautiful of woods!
~Tanner~
March 22nd, 2013 at 12:17 pm
Where does the name, Cocobolo come from and what does it mean?~Trevor
March 26th, 2013 at 10:19 am
A few days ago I bought another blank made of Cocobolo but instead of a dark piece I got a light one, can this color change? What color could this shift to?
March 26th, 2013 at 2:00 pm
Each and every board varies greatly in color and grain. You most likely got a piece of heart-wood, which from my experience is a hue of beautiful oranges, browns, greys, blacks, and even sometimes a hint of purple blue or green. very rarely any green. Sapwood boards are your darkers boards considering it’s still growing and very oily.
Hope my contributions on this page are helping,
~Tanner~
April 3rd, 2013 at 2:23 am
Can Burmese rosewood look similar to cocobolo?
April 3rd, 2013 at 2:25 am
Eric how long can it take to grow one rosewood tree?
April 4th, 2013 at 5:40 pm
I have read that Cocobolo contains color/oils that when applying a finish will bleed into other woods can this color/oil be used effectively to stain wood? Just wondering.
~Trevor
April 4th, 2013 at 6:45 pm
I’m not sure how long it takes for a rosewood tree to mature to harvestable size, but I’d guess at least a few decades, if not longer; they’re very slow growers. I know some rosewood trees in Madagascar that were illegally harvested were said to be several centuries old.
As for Cocobolo oils and staining: not really practical to do that, as I’m sure there are easier and cheaper ways to obtain dye colorants.
April 4th, 2013 at 8:35 pm
It takes just around 80 years for a Cocobolo tree to mature to harvest-able size.
April 4th, 2013 at 9:47 pm
Dear Eric I have made a stain! This could be a really big seller! How much would you pay for natural wood-oil stain? Did I mention its water resistant? The color is bright orange-yellow and it smells great!
April 23rd, 2013 at 11:05 am
I recently purchased a beautiful bowl of Cocobolo. The grain and color is the most beautiful I have ever seen.
However: I have been warned that it will blacken over time and this really bothers me. A friend showed me a bowl he turned 15 years ago and it is so black you can hardly see the grain pattern.
Is there a finish that I can apply that will preserve the color and luster?
April 27th, 2013 at 11:23 am
i have recently been turning several items in cocobolo and have had a massive reaction to this wood it has total stripped the skin from my face and numbed most of my facial nerves it also penetrated my arms etc be very careful with this wood even though I was using face masks etc. it was not sufficient protection, this condition has lasted for two/three months and has taken a hell of a lot of clearing up, so once again please be very careful. All the best.