As a woodworker, when you consider the wood that you are going to use, the weight of the wood is one of the prime considerations. You have to handle the wood, carry it around and work on it. The weight of wood is directly proportional to its hardness and density. Therefore, the harder and denser the wood, the heavier it will be.
The heaviest types of wood are also the strongest. However, they can be difficult to work with as they are denser and harder. But the advantage of items made from heavy woods is higher mechanical strength and longer life. Also, the hardest woods yield some of the best finishes. Most woodworkers consider working with the hardest woods a worthwhile challenge.
Relation Between Wood Density, Hardness, and Weight
Wood is a porous material. You could compare it to a sponge. The greener the wood, the higher the water content. It means that greenwood is the lightest, but as it dries, it becomes brown, darker, denser, and heavier.
As we mentioned above, the denser the wood, the heavier it is. Density is also directly proportional to hardness. We measure the hardness of wood through a test called the Janka hardness test.
We perform the Janka hardness test by impacting a steel ball on the surface of the wood. Then, we measure the dimensions of the impression made by the ball and convert it to a number that represents the Janka rating. The higher the number, the higher the Janka rating and the harder the wood.
Heaviest Types of wood
Here are some of the heaviest types of wood. As we mentioned above, the woods with the highest Janka hardness rating are the heaviest ones:
Black Ironwood (Krugiodendron ferreum)
You will find black ironwood, also known as leadwood growing in Central America, Southern Florida, and the Caribbean. It also grows in the forests in the Knysna region of South Africa. The trees grow only up to a height of 30 feet but the trunks are rather wide with a diameter of up to 5 feet.
With a Janka hardness rating of 3,660 lbf. black ironwood is a fairly hard type of wood. It is among one of the densest and heaviest woods in the world. You will find it difficult to work with due to its extreme hardness. The trees are small compared with other hardwood trees. So, you can only get smaller sections and make smaller projects with this wood.
This wood is not readily available because of the small size of the lumber, making it impractical for large projects. Because of its extreme hardness, ironwood is often compared to metal. The high density of ironwood makes it sink in water rather than float like most other types of wood.
Itin/Caranda (Prosopis kuntzei)
You will find this wood growing in South America in the Gran Chaco region. Itin also goes by the name Caranda. The trees are short and grow only up to 35 feet and the tree trunks up to diameters of 2 feet.
Itin has Janka hardness rating of 3,200 lbf. It comes under the category of mesquite trees. It gives off a characteristic odor while being worked. This wood also serves as a viable alternative to ebony because of its heavy dark color and texture.
Itin is not a species that is at risk and is widely available. We use itin for flooring, furniture, and for making cabinets.
African Blackwood (Dalbergia melanoxylon)
Here is another extremely hard type of wood with a Janka hardness of 3,670 lbf. The trees grow in the dry, arid regions of Central and Southern Africa. African Blackwood trees grow up to 30 feet with tree trunks of up to 3 feet in diameter.
The heartwood is so dark that it has no discernable grain pattern, although you may see purplish shades in the wood grain. Proven to be an extremely hard type of wood to work with, we use African blackwood to make musical instruments. It responds better to turning than to cutting.
African blackwood is categorized as a near-threatened wood species because of its slow growth cycle and overharvesting. Due to this, the lumber of African blackwood is scarce and highly expensive. This wood is often considered as the first true ebony, although does not belong to the original ebony species. True ebony is slightly lighter, less dense, and easier to work with than African blackwood.
Lignum Vitae (Guaiacum officinale/G. sanctum)
Lignum Vitae is native to South America. The trees grow to 30 feet with tree trunks growing to a diameter of 2 feet. It is one of the hardest woods that you can get with a Janka hardness rating of 4,390 lbf. The wood is dark brown with an olive-green tint. It comes under the category of exotic hardwoods
The wood has a sufficient level of natural oil to give a naturally-high luster. It is extremely resistant to rot, so it can be easily used for outdoor applications. Lignum vitae is an endangered species of wood due to overharvesting over the years.
Because of its extremely high density and hardness, it is a difficult wood to work with. Cutting blades tend to skip over this wood, therefore you need to use extremely light passes when you are using high-speed blades on this wood.
It is difficult to glue lignum vitae due to its highly oily surface and for the same reason, you will find it challenging to apply any type of finish to it. This wood is more of a turning wood rather than one that you would cut.
Quebracho (Schinopsis spp.: S. balansae, S. brasiliensis, S. lorentzii, S. quebracho-colorado)
Quebracho also known as quebracho Colorado or red quebracho is a wood that has several sub-species like S. balansae, S. brasiliensis, S. lorentzii, and S. quebracho-colorado.
It is native to tropical South America and the trees grow up to 50 feet with tree trunk diameters of up to 3 feet. It has a Janka hardness rating of 4,570 lbf. This wood is the hardest type of wood on this list.
Quebracho wood has a beautiful reddish appearance that blends into a deep, blood-red color with prolonged exposure to sunlight. Again, it is an extremely hard type of wood and earned the name of “ax breaker.” This term alludes to the Spanish name of the wood.
We use Quebracho for fence posts and railway ties due to its high resistance to rot, insect attacks, and also resistance to extreme weather. It is not an expensive type of wood in the United States but the imported varieties can cost considerably more.
Quebracho is not an endangered wood species. It used to be at high-risk sustainability when it was popularly used in the leather industry. But with the decline of the leather industry, Quebracho has become more available today.
Conclusion
These are just a few of the hardest woods in the world. If you get any of these woods, do not hesitate to use them. However, you may have to exercise a bit of patience while cutting and machining it.
Although these woods are extremely hard, they are all well-known for their fine finish once done. So, if you ever get hold of any one of these woods, you can try them to make a fine woodworking project.
