Lignum vitae is known as “wood so dense it doesn't float.” You may not want to build a boat with lignum vitae, it's true, but it has served boat builders for centuries due to its hardness and resistance to decay and insects, perfect for parts of rigging needing great strength and durability.

Is there any wood that doesn't float?

Lignum vitae is a wood, also called guayacan or guaiacum, and in parts of Europe known as Pockholz or pokhout, from trees of the genus Guaiacum.

Does all wood float?

If you've ever dropped a chunk of wood in a pond or watched a log floating on a lake, you already know that most wood floats in water. Some wood, however, sinks. The important distinction is not that the wood is heavier, but that it is more dense than water. Most kinds of wood float -- but some do not.