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Pigment figure in wood

Author: Peter MacSween
Photos: Ella Mac Sween; Lead photo by Rob Brown
Published: February March 2023
pigmented wood
pigmented wood

It’s hard to imagine where the world of woodworking would be without figured wood. For thousands of years, exquisitely figured pieces of wood have inspired woodworkers from the Egyptians to the recent works of James Krenov and Michael Fortune.

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This column is the first in a series exploring figure in wood. We’ll look at the different types of figure, while also see­ing how the anatomy and structure of the tree creates these visual effects. I’ll also share some tips and techniques for working with these interesting figures.

This column is the first in a series exploring figure in wood. We’ll look at the different types of figure, while also see­ing how the anatomy and structure of the tree creates these visual effects. I’ll also share some tips and techniques for working with these interesting figures.

Let’s start with a definition and, as in previous articles, I turn again to R. Bruce Hoadley, author of Understanding Wood. He defines figure as “any distinctive appearance on a longitudi­nal wood surface resulting from anatomical structure, irregular colouration or defects.” It’s a useful description that includes the obvious (colour, curl, etc.) and the not so obvious (on a longitudi­nal wood surface).

The surface the figure appears on is important because how the wood is sawn or sliced can either reveal or emphasize vari­ous figures. Quarter cutting white oak will reveal medullary rays yielding the ray fleck figure. Bird’s-eye maple veneer is usually rotary sliced to produce similarly sized eyes that are uniformly distributed.

It’s also important that the figure be distinct. That piece of flat sawn white ash with nested cathedrals may be beautiful, but it’s not considered figured. It represents the norm and industry would call it plain sawn or, surprisingly, non-figured.

Brazilian Rosewood
These two goblets, made of Brazilian rosewood, show the rhythmic pattern of vertical dark black and lighter browns stripes that make for a very striking visual effect.

Brazilian rosewood

Zebrawood
Some species of wood look drastically different depending on whether they’re flat cut or quarter cut. Here, zebrawood shows off its quarter cut pattern of dark and light stripes on the wider face, while showing a very bland surface on its flat cut edge. (Photo by Rob Brown)

Zebrawood

Macassar Ebony
Similar to zebrawood, these two pieces of quarter sawn macassar ebony show very straight grain with lots of colour variation between almost black and light beige.

Macassar Ebony

Olivewood
The pigmented heart of this olivewood veneer is very rich and warm.

Olivewood

Ziricote
These two bookmatched pieces of ziricote veneer show how incredibly varied the grain of this species is. The darker, varied heartwood, mixed with the extremely pale sapwood, can create some bold effects.

Two main categories

Some experts break the various figure types into two broad cat­egories. The first category is called general figure. This is a bit of a catchall category, and it includes pigment figure, burls, crotch fig­ure, ray fleck and a few others.

The second category is called specific figure. These figures derive from three circumstances: figure from spiral growth; figure from wavy growth; and figure from indented growth rings. Here we find the familiar figure types like block mottle, ribbon stripe, fiddle back, quilt and bird’s-eye.

I often think there should be a third category reserved for figure produced by outside agents acting on the tree itself. This would include figure produced by animals such as birds and insects and their larvae. Fungi produce interesting visual figure as well, with English brown oak being a good example. One could, of course, include humans since we colour and physically manipulate wood.
So, let’s start with the general figure category, focusing on pig­ment figure.

Pigment figure

As trees mature, sapwood in the trees transition to heartwood. This transition is accompanied by the deposition of chemicals called extractives into the cell walls of the heartwood. These chemi­cals are there to offer protection from fungal decay. The compounds are often coloured and they give the heartwood of many species a distinctive colour and pattern.

Pigment figure results when the extractive pigments yield ran­dom or regular patterns in the heartwood. The sapwood never sees the pigments and in hardwoods usually remains a pale white to tan colour. That board of purpleheart you have doesn’t count as pig­ment figure since all boards of purpleheart are uniformly purple.

The rosewood family contains many species showing pigment-fig­ured wood. Brazilian rosewood shows various patterns from spider webs to very abstract patterns. Other rosewoods, such as cocobolo, show broad washes of orange and red in the heartwood.

Zebrawood is another well-known wood with pigment fig­ure. The flat sawn or sliced surface is rather nondescript, but the quartered or radial surface shows a vertical pattern of alternat­ing bands of colour. Macassar ebony also reveals a similar pattern when quartered. The very best and rarest Macassar ebony shows a precise comb-like pattern of vertically alternating bands of black contrasting with a creamy or pale white.

Good examples of irregular pigment patterns are found in olive­wood, ziricote and red gum. Olivewood produces a pattern of wispy interwoven shades of colour. Ziricote is one of my favou­rites. Here the pigments produce a stunning pattern that resembles billowing clouds.

Manitoba maple is another wood with pigment figure that mean­ders through the heartwood. Once thought to be the result of a fungus, recent research has shown it to be a chemical produced by the tree when it is under insect attack.

Pigment figure can sometimes affect how a board is worked. Woods like red gum work easily by hand and machine. On occa­sion, extractives can be abrasive and can dull your tools quickly. Macassar ebony, already tough and dense to begin with, is challenging to work once its abrasive extractives are included.

A genuine concern is how to preserve these beautiful colours. Exposure to air and light will cause all colours to fade. Any fin­ish with UV inhibitors is best but will only delay the fading of colours. Over time, the linear patterns lose the contrast between the dark and light regions and the irregular patterns will see a loss of definition.

It’s a good idea to use models and drawings when designing pieces with pigment figure patterns. Scale is important. A figure that works well in a small box may seem out of place when show­cased in a cabinet on a stand. Take your time and have some fun with your chosen material as you build a working knowledge of various types of wood figure.

In my next column, I’ll continue to examine woods with general figuring, taking a closer look at burls. Burls have a long pedigree in woodwork­ing and I think may be the most beautiful of all figure types.


Peter Mac Sween - [email protected]

Peter's woodworking journey began with a career in carpentry followed by a decade buying and selling veneer. His spare time is spent abusing his guitars and exploring the great outdoors.

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