The internet has enabled people to have their dream instrument built with the finest material, but it's does require a careful, through screening process to ensure you get fair value. Selecting Brazilian rosewood for guitar making is not as straightforward as you might think. I will try to give you some insight from my own 21 years as a tonewood dealer and part time guitar maker, drawing comparison between old and new growth materials.
"Old Growth" has to be the most abused descriptive term in use when describing lumber and wood. Every piece of rosewood is "old growth" even when it's obvious that is came from a tree only 12-15in in diameter with the tell-tale "whitewood" on either side. That "whitewood" is called the sapwood, it occurs on all trees, it just that on large old growth trees it's the first thing to be cut off and discarded. On small young trees it's often times left to give the finished boards additional width. Sapwood on a truly old growth set can add dramatic contrast and although there have been and still are top quality instruments being made that feature portions of sapwood, it is a good indicator that the set may be new material. On "Old Growth" material the growth rings should be closely spaces, i.e. slow growth, that occurred in a forest, competing with other trees for limited sunlight, nutrients etc. I like to keep the rings fairly tight, say no more than 1/8in. in width. For truly fine old material the closer the better, as this is a good indicator of density. I'll give more details further on, for now just remember wide grain spacing means "new" growth material.
Old growth rosewood's color should be deep, rich even color that can range from dark brown, brick red, orange (yes, orange) and even black. In the best old growth material this color is complemented by black wispy ink-like lines often called landscape grain or spider webbing etc. This wonderful color and figure is the result of a mature tree's production of chemicals called extractives, which protect the heartwood from insects etc. I was told by a very, very old classical builder who had many years experience buying Brazilian rosewood in the 1950's and 60's that only when a very large tree starts to reach the end of it's life does it produce the truly wonderful colors so prized in Brazilian rosewood. He also told me that very black wood comes from logs sitting in water for a prolonged period. Fungal agents will enter cracks; insect holes etc and impart a black color. Personally I love dark, mysterious rosewood. While I'm on the subject of color, one thing to watch for is that the final color can change dramatically after a piece of lumber has been planed or sanded. I've seen very dark material finish out very light in color and conversely very pale material emerges from the widebelt sander nearly black. I think oxidation can explain some of this. Just keep this in mind, it doesn't happen often but it does happen. Finally, compare the back and sides closely in terms of color, grain and figuring matches. On the best guitar sets the back and side should be identical (from the same board). At the very least the color tones, growth rate (i.e. both old growth) should be the same. There are exceptions of course where a dramatic difference between back and sides can be visually appealing, but that is fairly rare. In terms of value a perfect match will always be worth more.
Old growth material is usually dense to very dense. The most consistently dense material I've seen has been the very dark brown or near jet black material. Density goes hand in hand with musical resonance and a higher transmission rate for sound waves called the velocity of sound. I've seen brazilin rosewood that rang like plate metal when tapped, with a long sustained ringing tone...bong........... There are exceptions, I've had some orange material that was of medium density and made wonderful guitars. What you want to avoid is light brown, dull, lightweight material that has no musical resonance.
After density, I look for the "cut" of the material; ideally guitarwood should be quatersawn or at least straight grained. That's not to say it can't have attractive, swirling backlines or streaks of color, just that the wood itself should be straight grained. Grain lines that look like the St. Louis arch are slabsawn material. Quartersawn material shrinks across its width and thickness evenly so even though the piece might change its dimensions slightly it doesn't warp. If you want a detailed explanation it's due to the tangential vs. radial shrinkage factors and how they are present in a quartersawn piece vs. a slabsawn piece of wood. Rather than go into details here, I'll just mention it. If your interested do a web search. The bottom line is that quatersawn material is much more stable and stability in guitar making is paramount. Warpage or non-uniform shrinkage can be a killer, when the back cups evenly slightly, it put strain on the top. (Remember they're connected via the sides). This can raise the top enough to change the string height, the break angle, playability and ultimately perhaps the sound. Dramatic slabcut wood has taken over eBay. Buyers are wooed by the beauty, however quartersawn material will always be more stable and a better choice for guitar making. In all fairness, much of the material I've seen lately is so old that slabsawn or not it's fairly stable. Why all the slab material?, Well it takes a very, very large tree to yield quartersawn material, it needs to be taken out like the spokes of a wheel i.e. the log is first quartered along it's length and these pie shaped wedges are then cut into boards. It's a slow and expensive process that requires a huge tree. Slabsawn wood is cut simply by slicing thru the log, from end to end, starting at the top and working down to the bottom. This method can utilize small trees and is much faster and less wasteful as every last bit of the tree is used and the log doesn't have to be repositioned after each cut.
Good, old growth Brazilian rosewood smells like the sugar they used to put on bubblegum we got as kids with our baseball cards. It's unmistakable in its light, floral sweetness. If you’re examining some rosewood and it doesn't have that sweet smell, don't panic, usually the smell will fade in time. A good test is to sand or scrape it lightly, that will usually give you change to get a good sniff. Indian rosewood smells pungent, somewhat sour and can even be unpleasant, resembling a well used men's room. I avoid any "Brazilian" rosewood that smells pungent/stinky; if it has an odor it should be sweet. Remember, it was called rosewood for a reason. If you've ever had the chance to mill old growth lumber it really does smell like roses. An interesting aside, often freshly milled rosewood will have a vivid reddish/pink color, placing the freshly cut pieces in direct sunlight will quickly render the final color. (If you try this be mindful of excess heat, watch the material closely and turn it often as it can warp quickly.)
The last and perhaps most overlooked consideration when buying a guitar set is the dimensions and physical suitability for guitar making. Sets that are severely warped, have thin spots with sawing marks should be looked at with caution. Saw marks can take a surprising amount of material to remove as there often times seems to be a deep scratch or two that just won't come out. The rule of thumb is backs should be approx. 3/16ths in the rough, finishing down to approx. 1/8th with saw marks removed. Sides should be approx. 1/8th in the rough, finishing out to approx. 5/64ths to 3/32nds (ideally .080in.) with saw marks removed. Saw chatter can make a piece of guitar wood worthless. Chatter is cause by harmonic vibrations/resonance that occures when the factors of feed-rate, blade speed and wood density all were just "wrong" causing the blade to oscillate side-to-side in the cut leaving deep ruts in both faces. All fine guitar sets should be thicknessed by an widebelt sander or abrasive planer, not a standard thicknessing planer. Even though a standard planer is much faster it can reduce a guitar set to splinters in seconds. Some warping can be relatively harmless if it is a smooth, continuous curve that will easily press flat, but if the stock is still heavy in thickness and needs to be abrasively planed to near final thickness, a heavy warp can make this difficult. A set that is wavy or "potato chipped" is usually impossible to work with. Some choice sets are passed up due to a jagged or excessively rough edge/outline for the rough cut set. Since anything outside the pattern will end up on the floor, rough edges or cracking etc outside the pattern really doesn't matter that much, as long as there is approx. 1/4in. overhang all the way around. It's amusing how many sets don't sell for much because they don't look pretty in the rough. Read on because I'm not talking about defect but rather how coarsely the set was cut down to approximate size. Oversized sets sometimes look bad due to knots etc. outside the pattern, novice buyers seem to give them undue weighting when choosing guitar materials.
When you find material that meets all of the above characteristics does that mean it's suitable for guitar making? Maybe, now you need to carefully look for cracks, knots, checking, wormholes, splits and punky areas. Some of these defects can be fixed but that will add to the build time for your instrument and can add to the finished cost. Some things like many fine cracks, jagged splits/cracking or punky areas are best avoided. Also isolated areas of dissimilar color can be deal breakers, just ask "do I want a large black spot (or light colored spot for that matter) in the middle of my expensive guitar". It won't get any better looking over time so keep that in mind. Knots can range from solid and sound to loose, cracked and unrepairable. While I'm on the subject of knots, a common defect that is cause by knots is the knot shadow. A knot shadow is a long issolated portion of dissimilar grained wood that often times appears as a kink in the grain, sometime with a different sheen when compared to the surrounding wood. It occurs when the cut intersects a branch (i.e. knot) along its length. Keep in mind that is has many of the same limitations as a common knot and may cause a problem in a back, but should be avoided if at all possible in side material. From a builder’s perspective, other deal breakers are knots in the sides that fall right where the sides need to be bent. Knots and bends don't coexist very well. If you're buying expensive material to have your dream guitar made I'd get the builder involved BEFORE you buy. Also, simply supplying the material doesn't mean that you'll save the entire up charge for Brazilian. Builders need to take extra care with expensive materials to prevent mishaps, misdirection or mistakes. If something was to happen to your prized material the builder couldn't just grab another set off the shelf and keep working. Even if the builder is the most careful in the world, he'll have to put an extra effort in to ensure that your wood ends up on your guitar! It may sound silly but that adds another chore to the process and the builder should be compensated for the nuisance factor. With all these potential difficulties why is old growth rosewood sought after, because it has all the characteristics needed to build a top notch musical instrument. It's resonant, dense, and beautiful and has a long historical precedence in lutherie. It also came from very large trees that aren't around any more hence it's scarce so what mature material we have in this country has become expensive.
When one talks of Brazilian rosewood a subject that always comes up is CITES certification. I'm not a lawyer, legal expert, U.S. Customs or Fish and Wildlife agent. What I'm telling you is only my general understanding; do not take it as law. It is not given as any sort of legal advice and I assume no responsibility for its accuracy. If you’re in doubt research it yourself. CITES stands for The Convention for the International Trade of Endangered Species... What it amounts to is a collection of governments meeting every few years and formalizes an agreement that regulates and controls the trade of endangered plants and animals. I know of three levels of classification, I, II and III which correspond to how "protected" a species is. As long as an item remains in a particular country it requires no CITES involvement, however once it crosses the border there can be stringent requirements. Brazilian rosewood is listed as CITES level I, the most restricted. As an aside, Honduran Mahogany has been recently upgraded from level III, which allows monitored free trade, to level II which requires import/export documentation. Level I items, require extensive documentation and CITES permits, to be issues by the US Fish and Wildlife agency AND corresponding foreign agency, BEFORE shipping. This permit is absolutely required for commercial trade, I don't know of any exceptions and would be very skeptical of anyone who claims to have CITES approved material. My understanding is that the permits are not easily obtained and that you must be able to prove with absolute certainty that the material was harvested before June 1992. In a real practical sense, how does one do this? For this reason alone, I do not buy or sell Brazilian rosewood internationally.
In the last 8-10 years there has been a complete change in how guitar materials are brought to market. I entered the Brazilian rosewood market in early 1990, at that time the only sources for quality materials were individuals who had stashed away very old lumber or a few guitar sets here and there. Lumber was from old cabinet shops, private parties or guitar sets usually had been rejected by a major manufacturer for some reason. Wormholes, minor cracks, being dimensionally out of specs (usually thickness) for a production environment were the major reasons these sets were culled. Despite these issues the material was still sound, old growth, with great color and usually very well quartersawn and nearly all of it could be repaired (guitar factories couldn't disrupt their work flow to do these repairs). In the mid 90's new sources for tonewoods had emerged. The most significant was the recovery of off-fall and stumps from past logging operations in Brazil. Since this material had obviously been harvested years ago export permits could be gotten. This material was usually of high quality but coming from the base of the tree had its own issues. For one, the grain at this transitional area often times was "wild" with a dramatic appearance but with border line stability. I know one builder who lost 4 out of 11 sets to severe cracking, all of them were "stump wood" and all were strikingly beautiful. With that said, cracking etc. usually happens during the initial air drying process, finished instruments, when built under the proper conditions rarely experience this sort of cracking. This wood is usually straight grained with a book matched broadly sweeping curve. Another new source of material was poaching. It was very easy to claim that your poached materials were also from reclaimed stumps. A trained eye could tell that these guitar sets were in fact from immature trees due to wide grain lines, only fair color and having been slab cut. Since these new sources had such high visibility they now became what people thought of when one said "Brazilian rosewood". Ironically the truly fine, old growth material had now taken a backseat to slabcut, wild grained, sap-wooded guitar sets with old growth sets going unsold on eBay while slabsawn new growth sets were commanding high prices. I've noticed that now private guitarwood buyers are maturing and are demanding better materials. The market is making strides towards a proper value/quality/price ratio.
I want to mention that Dalbergia spruceana is a common look alike for Brazilian rosewood. It can be almost identical to true Brazilian but is lacking that sweet smell. In addition to spruceana there are many other "look-a-likes" out there. I often see Indian rosewood being described as Brazilian. Usually it very old fine material that does resemble Brazilian since its purple/violet shades have oxidized into browns. I've seen samples of rosewoods that I couldn't determine precisely what they were, I walk on those buying opportunities. If you want to scientificly identify material I highly recommend Bruce Hoadly's "Identifing Wood". It will guide you through the correct scientific methods to determine what species your looking at. It also has a ton on useful information on other wood topics.
Personally I compare all potential purchases to Martins golden period, the mid 1930's. Wood that looks like it belongs on a 1937 D-28, D-45 or early 30's OM commands the highest prices. I strongly recommend studying as many old guitars as you can before shopping for guitar materials. Back in the day, builders could choose any thing they wanted. Many custom cut material from the log and with very few exceptions they choose uniform, straight grained, defect free stock. The "figure" came from the spiderwebbing not from irregular growth lines. It's a small point but an important one.
I want to state that nothing is black and white, it's not a case of old growth good...new growth bad... In many cases it's new growth rosewood good, old growth rosewood much better. Good instruments are being made today with newer growth, partially slab cut materials. These instruments are fine quality in their own right. I don't make direct comparisons between old and new growth material as they are quite different, both sonically and visually. Each piece needs to be carefully examined using the above criteria.
You may wonder where I fit into all this? Well I do have a limited brazilian rosewood inventory and yes this material is for sale. You might be surprised to learn that most of what I have is partially slabcut material, old growth mind you, but slabcut none the less. So this article isn't any sort of sales pitch, as I've done a fairly good job of elevating quartersawn stock over slabsawn material. I really just got tired of all the misinformation and distortions that have appeared in a number of private sources and felt that I could help by sharing what I have learned on this topic though my long time association with several retired CF Martin employees who had first hand knowledge.
If you've found this guide informative please vote, if not please contact me with any suggestions or improvements.