Textiles & Materials

Jason Lamberth

Jason Lamberth
Jason Lamberth Jason Lamberth

The Talisman of Hardwoods: Borneo Ironwood

Eusideroxylon zwageri, is one of the four species of the genus. It is known colloquially in English as Borneo ironwood and occasionally bilian ironwood or bilian. Other Common Names include Tambulian Tagalog, kayu ulin and belian Indonesian.

Ironwood is one of the worlds hardest and heaviest woods: harder, heavier and more durable than Teak, Ebony, Mahogany or Iroko, and one of the most exceptionally naturally durable hardwood species in existence. In the 2005 Australian standards report on Timber Preservation and Durability Ironwood achieved the highest durability ratings out of all the woods studied (including Burmese Teak).

In the same report Ironwood was given a probable "marine-borer-resistance" life expectancy of 60+ years in southern waters (shorter in tropical waters). This resistance estimate is for untreated/unprotected timber. Therefore with proper maintenance and use of anti-fouling protection, Ironwood hulls will likely last for 100 years or more.


The wood texture is fine and even, with a straight grain or only slightly interlocked. The timber retains a pleasant lemon odour. This odour along with the woods' natural high lustre make it prized by cabinet-makers and fine furniture craftsmen.

Fire Resistance

Another property of Ironwood is its very high density (0.85 – 1.1 g/cm³) ,which means that it would overwhelmingly satisfy the criteria for fire retardant timbers in Australian Standards 3959 on the Construction of Buildings in Bush Fire Prone Areas.

Also attractive to users is the Ironwood resistance to insects, bacteria, fungi and marine borers. The wood has anti-bacterial properties (for local medicinal use).

Limited Reclaimed Supply

Ironwood is native and endemic to Indonesian and Malaysian Borneo, and the southern Philippines. However, it is increasingly scarce, in most areas protected. Harvested ironwood is no longer available on the international market thus adding value and distinction to this found timber.


Vintage quality: Original cracking and imperfections are included. Natural erosion can vary. Only usable planks will be sold but client may have some waste due to need or taste.

Selected quality: Only the top quality planks with the best erosion and minimal cracking are hand-selected.