Crystals forming in wood stove ash

[jlax27]

Ever seen this before? My ash has been forming into a rock and these even have colors and crystals. Maybe the color is from news print?

 

[BrotherBart]

What wood? What stove? How hot ya burning it?

 

[Bioburner]

What are you burning? Some conifers carry large amounts of copper sulphate-blue. Sometime bark can carry large amounts of silica. The brown could be from iron-ferric oxide
Set up your signature please with stove details. Welcome

 

[Dix]

Are you burning glossy paper?

Need more input, like Johnny 5 !!

 

[peakbagger]

That's an example of ash fusion. Every blend of wood has an ash fusion temperature and contaminants can lower it. One a wood stove its not normally an issue but can sure raise heck with superheater and generating banks on industrial boilers.

 

[realstihl]

Elm does it the worst. It doesn't seem to burn any hotter than other wood.

 

[DanCorcoran]

Those are diamond seeds...leave them in there and they'll grow into real diamonds! (Keep this to yourself, though, for security purposes).

 

[jlax27]

Recently I have only been burning red oak with a bit of punk on the outside. Occasionally I use some pine to start the fire. I don't hesitate to burn bark but never in large quantities. Jotul f45 and typically run with top plate temperature between 400-500F. I took a bit of the crystals and put them back in as seeds. The ash has certainly been fusing as I haven't had to scoop it out in a couple weeks since I changed my wood source. I hope someone tells me my wood source is going to burn and make me diamonds!

 

[pma1123]

I've occasionally noticed crystallized ash chunks this year also while using the coal rake and having to bust the chunks loose. None looked quite as vibrant in color as the ones posted, but I have noticed some blue-ish looking hues. This years wood has been Elm, ash, boxelder, cherry, and silver maple. I wasn't sure which species to blame it on.

 

[Charles1981]

Well this is kind of blowing my mind...

 

[begreen]

Do a search on "clinker" in this forum. There are lots of threads on this topic.
https://www.hearth.com/talk/threads/biggest-clinker.79475/

 

[S Roche]

After reading the above and the posts in Begreen's link I noticed a couple of things I believe are related to the clinkers I find in my stove. They are directly in front of where the combustion air enters, and I did not notice them until I started burning barkless Red elm. I have never seen it with Green ash, Honey locust or Mulberry. There is a small 2" by 2" by 1/2" thick spot that feels as though it is fused to the firebrick. I'll deal with it when the burning season ends.

 

[spirilis]

I burn wood briquettes (liberty bricks, ala biobricks) and get huge "clinkers" all the time in my stove, but none as colorful as that! Very cool.

 

[jlax27]

S Roche. Now that you mention it I may have burnt some mulberry that my buddy gave me. That was prior to the red oak but maybe there was still ash in there from the mulberry and now that I'm burning the oak it may have got much hotter and fused.

I have never seen it with Green ash, Honey locust or Mulberry.

 

[jlax27]

Do a search on "clinker" in this forum. There are lots of threads on this topic.
https://www.hearth.com/talk/threads/biggest-clinker.79475/

I don't see any clinkers posted that look remotely like mine.

 

[begreen]

You must have the secret sauce.