They Don't All Float

A friend recently texted me with some photos of nice looking wood that someone was selling on facebook. He had asked the seller if the wood floats or sinks in water, and the seller replied "All wood floats".
This told me the seller probably doesn't know what he's talking about, and I advised my friend accordingly.
It is a common misconception that "all wood floats." Most trees produce wood that floats, and boats are known for traditionally being made of wood. It seems intuitive that wood floats.
But woods from different plants vary in physical characteristics, including elasticity, hardness, and density. The variation in density includes woods that are both lighter and heavier than water. Balsa wood, which most people are familiar with from arts and crafts, is obviously much lighter than water. Even heavier common woods, such as oak or hickory, are lighter than water.

Then there are Ironwoods.

The term "Ironwood" does not refer to a specific species of wood, but rather to the hardest and densest wood from a given region. They are often slow growing, scarce, and highly valued. In general, woods considered to be "Ironwood" are denser than water. Put a piece in a pool and it will sink right to the bottom. 
All of the wooden wands used in the production of Makoto Street Wands sink in water. Our first luxury magic wand, the Lignum Vitae Street Wand, inspired by Cellini and the staff of Merlin, just happened to be a dense Ironwood that is functional for sleight of hand and cups and balls. In researching and experimenting with dozens of similar ironwoods and exotics, the other woods that were robust and beautiful enough for inclusion in our offering happened to sink in water. 
When people-- laymen and magicians alike-- feel ironwood for the first time, they are often surprised by the weight. An ironwood wand feels like it should be made of stone, not wood. It adds tactile enchantment to the audience's experience of your magic.
And if you teach them that not all wood floats and that your wand is made of a rare Ironwood that sinks, they will be a little more informed than the facebook seller my friend contacted.