OK. I found his treatise and will post most of it below. (long) Oddly, in scanning, I didn't see mention of Cumala. He must have talked about it in private messages to me. I don't believe he wishes to spread the 'joys' of hallucinogens to too many people. His name is Jim King, an American in SA in the exotic wood export business. Here is his link: http://www.exoticwoodworld.com/
Now as for what woods are valuable. Rosewoods are a great example of tropicals.
Read the article below: “THE ROSEWOOD JUNGLEâ€
Many tropical woods sold are sold as something they are not. Rosewoods are one of the finest examples as is well explained in the article below. There are two main reasons. The first is that there is very little knowledge about tropical woods and the identification is at a very primitive stage. The second is that a lot of wood is sold as something it is not either on purpose or by ignorance.
Now to make a long story short what makes some tropical wood valuable is the fantastic color and grain. Known or unknown species with , burls, roots, crotches, defect in the grain and color sell. Wood like Mahogany is cheap but is an old standard that somehow is equated with quality even tho is looks like cardboard and is still accepted in many markets but dying fast.
I could go on for pages but this should give an idea of what you were looking for.
THE ROSEWOOD JUNGLE
by Dick Boak, manager of the Wood Division of Martin Guitar Company, visit http://www.mguitar.com/.
INTRODUCTION
Rosewoods in general have been prized throughout history because of their richly exotic and vividly contrasting grain. In terms of sheer beauty, few woods can compete with Rosewood. There is however, a great deal of confusion and misinformation about the many varieties of genuine Rosewoods as well as the so-called "substitute" species. This article should clear up most of that confusion. In order for a wood to be considered "true" or "genuine" Rosewood, the tree must be a member of the specific genus Dalbergia (Leguminosae family).
There are many species within the Dalbergia genus:
GENUINE SPECIES
BLACKWOOD (Dalbergia melanoxylon) Africa African Blackwood, also known as Grenadillo or Mozambique "Ebony", is dark purple to black in color with similar density and working properties of true Ebony. It should not be confused with Granadillo, a Rosewood substitute discussed later in this article. African Blackwood is traditionally used in the construction of the finest wind instruments, bagpipes, violin bows, ornamental turnings and precious treen. It is very rare, very expensive and is generally available in small dimensioned pieces only.
BRAZILIAN ROSEWOOD (Dalbergia nigra) Brazil Sometimes referred to as "Jacaranda", this preferred species ranges in color from dark brown to violet with spidery black pigment lines that often overlap giving the illusion of landscape, hence the term "landscape grain". The smell is like roses when freshly cut. Brazilian Rosewood is the optimum species for the reflective back and sides of acoustic guitars. The species was so popular as sliced veneer for the furniture and plywood markets during the first half of the century that it has been driven to near extinction, though some sparse new growth timber has appeared on the market. The highly resinous wood turns beautifully, polishes well and is very durable. It is very expensive if available at all.
COCOBOLO (Dalbergia retusa) Mexico & Central America This highly exotic wild grained species is brilliant orange, rust, purple and yellow with distinctive superimposed lines of purple and black. The brilliant color seems to oxidize gradually with air exposure after cutting. Some woodworker's react specifically to the cinnomon-like sawdust that typically causes itching or sneezing. Nonetheless, the unusual vivid beauty and color contrast of this wood overshadow the allergic risks. It is typically available in small cuttings due to the relative small size of the tree.
EAST INDIAN ROSEWOOD (Dalbergia latifolia) India Predominantly light to dark purple, with occasional red and brown streaks, East Indian Rosewood is prized for it's consistency and it's size. When Brazilian Rosewood began to become scarce, East Indian Rosewood quickly filled the vacancy. The wood was more stable, met grade lumber specifications easier, and came in larger planks. Within the last ten years, embargoes and regulations have severely limited the sizes of East Indian Rosewood pieces allowed out of India. Some "plantation" growth of the same species is available as "Sonokeling" from Indonesia. Another close relative includes Dalbergia sissoo from the region in and around India.
HONDURAS ROSEWOOD (Dalbergia stevensonii) C. America Honduras Rosewood is pinkish brown to salmon red with dark irregular grain lines. It is very hard, heavy, and durable. It is difficult to dry and prone to heart cracking which causes poor yield, but after drying the wood is quite stable. Honduras Rosewood is highly regarded within the furniture and musical instrument industry for its beauty, its strength and its tone quality. It takes a trained eye to differentiate between Honduras Rosewood and Guatemala Rosewood, Dalbergia tucurensis or Dalbergia cubilquitzensis (two botanical names for the identical species).
KINGWOOD (Dalbergia cearensis) Brazil Kingwood, often referred to as Violetwood, is brownish purple with fine stripes of black and luminous violet that can approach royal blue. Appreciably denser than most other rosewoods, Kingwood is similar to Brazilian Rosewood in technical properties, but harder and stronger. The size of clear cuttings is very small but Kingwood works well and takes a high natural polish. It is especially popular for fancy trinkets and decorative marquetry.
AMAZON ROSEWOOD (Dalbergia spruceana) Brazil Also referred to as "Jacaranda do para" or "spruceana", this species resembles Brazilian Rosewood somewhat and is used for similar purposes, though odor and subtle grain characteristics are noticeably different. The pores are often filled with a characteristic yellow sulphur deposit. The trees are generally logged during Mahogany harvests in the Amazon River region.
TULIPWOOD (Dalbergia frutescens) Brazil Sometimes distributed as "Brazilian Pinkwood", Tulipwood has a rich pinkish golden hue with luminous salmon stripes. The general color is much lighter than any of the other Rosewoods. It is quite valuable and is generally available in small cuttings only.
COMMON SUBSTITUTES FOR GENUINE ROSEWOOD
Since the price of the genuine Rosewoods has moved out of the range of many buyers, many species that resemble Rosewood in color and durability have appeared on the wood market at prices which are up to half the cost of the genuine varieties. The more common of these substitutes are as follows:
BOCOTE (Cordia elaegnoides) Mexico Bocote (often referred to by its genus, Cordia) has contrasting black, green and golden yellow vibrant color with tight wild figure patterns. Commercially known as "Mexican Rosewood", Bocote is available in relatively small cuttings and the wood has a waxy texture similar to teak.
BUBINGA (Guibourtia tessmannii) Africa Often referred to as "African Rosewood", Bubinga is purplish pink to salmon red with dark red veining. A mottled or "flamed" figure is often seen in quartersawn lumber. Bubinga is very dense with a very fine texture and since the tree is quite large, the lumber is often available in wider planks. Thicker stock is difficult to dry and prone to kiln degrade from checking. Bubinga is used to make guitars:
GRANADILLO (Platymiscium yucatanum) Mexico Reddish brown to purplish orange dependent upon the source of origin, Granadillo (not to be confused with Grenadillo or African Blackwood) is a catch all term for a number of look-a-like species that have properties relatively similar to Rosewood (specifically Cocobolo), though the grain and figure are often more bland in comparison.
MORADO (Machaerium scleroxylon) Bolivia Morado, also referred to as Santos "Rosewood, Bolivian "Rosewood", or "striped caviuna" is a close Rosewood substitute though the general color is more brown than East Indian and more purple than Brazilian Rosewood, with occasional variances of yellow, red, or black. Morado has become popular partly due to it's price, which is considerably lower than any of the true Rosewoods. It has a pleasant fragrance similar to Rosewood and a very fine texture due to a very small pore structure. As a result it can be finished without the filling and resin problems that are characteristic of true Rosewoods. The sawdust is considered a skin irritant with effects similar to to Cocobolo dust. Jacarando Pardo (Machaerium villosum) from Brazil is very close in appearance to Morado and is probably marketed interchangeably with Morado, since they are of the same genus.
PADAUK (Pterocarpus spp.) Africa, Burma, Andeman Islands Often referred to as Vermillion, Padauk varies in color according to a number of variations within species, but most varieties will display a brilliant red orange color when freshly cut, with darker crimson grain lines. Upon extended exposure to light, Padauk can gradually turn to a dark crimson to walnut shade. It is a popular wood due to its striking color. It is easy to work and is often available in reasonable widths.
CATCH-ALL TERMS
The word "Jacaranda" is used regionally in South America for any wood, genuine or not, that resembles Rosewood. As a result, it causes a great deal of confusion in the wood market. Some of this confusion is purposeful, since uneducated wood buyers can often be easily fooled. The word "Granadillo" is used extensively in the Central Amarica and Mexico to market any of a variety of woods that have dark grain and are either difficult to accurately identify or have no marketable trade name. The word "Palissandre" or "Palissander" is another general term, typically overused in the European wood market, for any species of wood that "is or resembles" Rosewood. Several woods, similar in appearance, weight, and working characteristics are marketed under the general but misleading heading of "ironwood" or "Pau Ferro". Morado (Machaerium scleroxylon) is closely related and often referred to as Pau Ferro (Libidibia sclerocarpa), as are Brazilwood (Caesalpinia echinata), Maracaibo Ebony or Partridgewood (Guilandina echinata), Lignum Vitae (Guaiacum spp.), Mesquite (Prosopis juliflora), and a small gnarled shrub from the deserts of the southwestern US and Mexico referred to as Desert Ironwood. All are extremely heavy, some approaching the texture of petrified wood. Many of these woods have a dark heartwood that closely resembles the brilliant coloration of Rosewood. Ironwood is usually sought by ornamental turners and makers of jewelry and small treen.
BUYING CONCERNS
Unless you are dealing with companies or individuals that are both knowledgeable and reputable, you should be prepared for some misinformation when buying Rosewood. It is best to educate yourself by collecting samples and reading as much as you can about different woods. Several good books about wood identification have been published, though some are out of print. One of the most comprehensive wood books available is World Woods In Color by William A. Lincoln. MacMillan Publishing Co., 866 Third Avenue, New York, N.Y. 10022 ; 1986. $39.95, hardcover; 320 pp. This book contains accurate information on more than 275 different woods
HOAXES
In the stringed musical instrument building trade, Rosewood plays a very significant role as the undisputed ideal tonewood for the back and sides of acoustic guitars. Specificly, Brazilian Rosewood is considered the best species for this purpose, but this wood is also extremely rare and inordinately expensive. It is fairly common to hear stories about Brazilian Rosewood purchases that have been made, sight unseen, wherein the wood purchased is in fact from Brazil, but it is definitely not the desired item. This confusion arises for a number of different reasons. First and foremost, there are many species of "genuine" Rosewood from Brazil, so that technically a seller can stretch the truth by representing Kingwood, Tulipwood, Jacaranda do Para, etc. (genuine Rosewoods from Brazil) as Brazilian Rosewood. Personally, I know of one such incident involving a rather large quantity of guitar wood that arrived from San Paulo, Brazil as Dalbergia nigra. It would have fooled most novices, but not those with experience. Eventually samples of this wood were sent to the Forest Products Laboratory for identification. It came back labeled "Pitomba Preta", an obscure regional name for a wood that was not even a member of the Rosewood family. One sad aspect of purchases like this one is that it is often necessary to open a letter of credit in order to buy a parcel of wood in another country. This means you pay 100% in advance, and there is little if any recourse if you are dissatisfied, or worse yet ripped off!
Imagine a wood broker who has made a poor purchase. Perhaps a species has been misrepresented to him and he has been "stuck" with a particular load of the non-genuine item. How in the world will this fellow get rid of this wood, especially if the wood was bought as genuine Rosewood at a relatively high cost. It is not uncommon for brokers to "play dumb" and allow a misrepresentation to continue. In many cases, a broker will get a phone request for a specific variety of Rosewood, East Indian for example. If the broker doesn't have any East Indian in stock, but does have Amazon Rosewood, the broker understandably might try to convince the customer that Amazon Rosewood is what he really wants! Sometimes samples are sent of the correct species, then when an actual large order is placed, an alternate species is substituted. You might be appalled at how dishonest this is, but there can be a great deal of corruption in lesser developed countries (almost as much as in highly developed nations like our own), and once the ball starts rolling it's hard to stop it.
Within the last few years, a type of picture frame has hit the shopping mall market displaying a proud and prominent gold foil label stating "Made Of Genuine Rosewood". It is most likely that these cordovan colored bright red frames are made of heavily stained Ramin or perhaps Padauk, but they are not like any Rosewood I have ever seen. I watched one afternoon at one of the malls and they were selling like hotcakes, so I'm sure the stores are happy. The customers seem happy too, believing that they have acquired real Rosewood at a bargain price. Something is very wrong with this scenario, and there doesn't seem to be any direct way of dealing with this type of mis-representation. At our place of business, we are very careful to correctly represent each species for what it is. Through the years we have developed a system that we feel is quite straight forward. If we are selling a genuine rosewood species we simply list it as (for example): Brazilian Rosewood. If however, we are selling a substitute species (that is not a member of the Dalbergia genus) we list it as (for example): Bocote (Mexican "Rosewood"). The " " are there to let the customer know that the wood it a substitute, and we try to explain this whenever we are selling a substitute species. It is very important that wood brokers and hardwood distributors maintain a sense of integrity and honor when they represent a product. If they don't, the confusion they cause will eventually backfire in the form of claims or bad reputation.
CONCLUSION
Reading this article might give the reader the impression that there are so many quirks and concerns with Rosewood that it is simply not worth dealing with all of the problems. On the contrary, I enumerate these details to introduce you to some of the fascinating differences between these and other varieties of wood, and to encourage you to proceed without fear of failure. I know that if you have never worked with Rosewood you will find it a complete and wonderful indulgence. You'll be spoiled to the extent that working with mahogany or maple might seem a little boring. Hopefully the information given here will help you navigate through and survive the Rosewood jungle.
Dick Boak is the manager of the wood division for the Martin Guitar Company. He also operates the "Church of Art" which is a renovated multi-media art studio and residence in Nazareth, PA.
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