Yes, petrified wood can get wet.
The organic material in petrified wood has been completely replaced with minerals.
It’s a stone.
But for many reasons, we don’t recommend that you soak petrified wood in water for extended periods of time.
Why Can Petrified Wood Get Wet?
First and foremost, petrified wood is no longer “wood” as you understand wood to be.
Even though it still might look like wood, petrified wood is actually completely composed of minerals.
It is a stone made up of familiar minerals like silica (which is also the base mineral for quartz of all colors), as well as calcite and pyrite among other materials.
So you have to think of it in terms of the minerals that make up the material, and not as organic matter (that can decay and break down).
Petrified wood starts as wood.
But over time, water containing minerals leeches through the wood, and those minerals are slowly deposited into the wood.
As the organic material decays and breaks down so very slowly over a period of millions of years, the minerals replace the organic matter, so the appearance of the physical structure remains (like the growth rings and bark).
But when you place the petrified wood in water, the material does not absorb water like an organic piece of material would.
As a result, putting petrified wood into water for brief periods of time (like to clean it up) shouldn’t do it any harm.
Why Don’t You Recommend Putting Petrified Wood Into Water?
We generally recommend against putting petrified wood into water for extended periods of time because water can often cause damage to the material.
Water Can Weaken the Material, Or Cause The Material To Crack or Break
Minerals, gems, and stones of all kinds contain fissures/cracks.
Sometimes those cracks are easy to see, and sometimes those fissures are too small to see.
When when you put stone in water, the water molecules find their way into those cracks.
Those water molecules will make those fissures slowly wider.
Over time, this can encourage the stone to crack apart or break.
This is unfortunate, especially if you have invested significantly to make the petrified wood into a table, sculpture, or something else valuable to you.
Petrified wood often gets its color from the presence of metals.
Sitting in the water or allowing the piece to be consistently wet can encourage the formation of rust, which can leave the piece looking yellow, which a scrub won’t solve.
If left wet for extended periods of time, that yellowing can turn into a reddish brown stain that cannot be easily removed.
You’ll be stuck trying to use acids or other products to try and return the stone to its original brightness.
Sometimes all you can do is cut or grind the rusting off.
The links in this article to products are links to Amazon. As an Amazon affiliate, we may earn a commission from qualifying purchases at no additional cost to you.
Damage To The Finish
Sitting in water can also damage any finish work done to the petrified wood, if it had been professionally or purposefully shined up and shaped.
Many minerals sold commercially are coated with a thin layer of a product to make the stone looking brighter and shinier.
Some of these are oils, which have to be reapplied from time to time.
Sometimes these commercial products are tinted, to make the stone look nicer.
Either way, when these products are stripped off, your stone can’t help but look duller underneath.
Water can also damage the natural shine of the stone, as the water molecules infiltrate the surface of the stone, so light doesn’t refract the way it did before.
Water soaks can also cause other changes to the surface colors of the stone that only cutting or grinding can fix.
We often hear of disappointed collectors who soaked their finished mineral in water (or even salt water) because they heard it was good for the stone, good for their home, or to clean/cleanse it.
The stone they pull out rarely resembles they beautiful one they put in, and they do not have the knowledge or equipment to fix it.
Sometimes it is impossible to understand exactly what your petrified wood is made up of.
There could be toxic materials in the stone, or metals that react badly with water.
Some of these chemicals leech out into the water, while others actually produce a toxic gas into the air.
Just because the surface of the piece looks safe, doesn’t mean that there isn’t something hidden inside that the water can reach and react with.
How To Clean Petrified Wood
In general, when working with minerals, the best method to first employ to clean your petrified wood is by using a soft cloth and your hand to buff the material.
Can the material be rubbed clean?
If not, then you can move to a damp rag, getting the rag wet (and not pouring water on the stone), and rubbing the stone.
Avoid using hot water.
If the appearance issue does not improve, move to a damp rag and a mild dish soap, then use the wet rag to rub/buff clean.
If after cleaning with soap and water, the stone is still not clean, you have the choice is trying to soak it in water (or other products), or applying a product by spraying it.
People have good results with some of these methods, but when it comes to using acids, we would prefer to see if the exterior issue could be ground off (with a dremel, for example) over employing chemicals.
This is especially the case if you petrified wood is quite large, and the only spot you want to clean up is pretty small.
In general, we think the best way to clean up petrified wood is to just do what is minimally invasive.
And if that doesn’t work, consider leaving the stone the way it is, or proceed at your own risk with chemical processes.
We just don’t like them/use them.