First two videos are TTBVI. Mushroom hyphae are boring compared to most contams, but if you’ve not seen it before, here it is.
The third and fourth videos are a beautiful contaminant. (brownish colored light background, focusing through layers of hyphae that look like studded whips)
When looking closely at Panaeolus cyanescens, you might notice tiny, glittering structures clinging to the mycelium or the base of the mushroom. These aren't just dust or debris; they are a fascinating biological phenomenon known as biomineralization.
What is Biomineralization?
Biomineralization is the process by which living organisms produce minerals to harden or stiffen existing tissues. While we often think of this in terms of "charismatic megafauna"—like the calcium phosphate in our bones or the calcium carbonate in sea shells—fungi are master mineralogists in their own right.
In the fungal kingdom, this most commonly manifests as the formation of calcium oxalate crystals. While this specific process hasn't been a primary focus of academic literature regarding P. cyanescens specifically, its appearance here is not at all surprising. Biomineralization has been documented across a vast array of mushroom species and is a standard tool in the fungal utility belt.
The Science of the Stone
The crystals you see generally appear in two primary mineral forms:
• Whewellite: The monohydrate form (\bm{CaC_2O_4 \cdot H_2O}).
• Weddellite: The dihydrate form (\bm{CaC_2O_4 \cdot 2H_2O}).
Why Do Fungi Build Crystals?
Evolution rarely does anything without a reason. For a mushroom, "growing rocks" offers several distinct advantages:
• Defense: These jagged crystals can act as a physical deterrent against micro-grazers like springtails or larvae, making the fungi a much less appetizing snack.
• Calcium Regulation: Fungi use this process to manage internal calcium levels, sequestering excess calcium into a solid form to maintain cellular balance.
• Environmental Modification: The production of oxalic acid (the precursor to these crystals) helps the fungi break down organic matter and access nutrients in the surrounding environment.
A Note on "Kidney Stones"
You might recognize the term "calcium oxalate" because it is the primary component of most human kidney stones. While the chemical name is the same, the context is very different. In humans, these crystals often form in urine due to metabolic imbalances or dehydration. In fungi, however, it is a controlled, functional biological process essential to their survival in the wild.
Seeing these crystals on P. cyanescens is a beautiful reminder that even the smallest fungi are active participants in the earth's geological and chemical cycles.
First off, I am making this post because it’s the right thing to do by my favorite LC vendor.
If any of you buy LC from an EXCELLENT LC vendor, and you’re of a mind to check your LC under a microscope before you use it, and it’s loaded with yeast, don’t lose hope. Some of the BEST LC vendors out there shipped me three syringes, three different strains, that were all loaded with yeast. Identical looking “contaminants” in all three.
The microscope has a camera, obviously. It turns out that the yeast were dead, and that the vendor uses nutritional yeast in the broth. It only takes the small amounts that people put in agar to make it appear to be heavily contaminated, but those with scopes already know that.
I had methylene blue on hand, the stuff that RFK Jr. puts in his drinking water. It’s a pretty common quack remedy, and there are lots of quacks on these forums , so I’m not being obnoxious by acting like someone might have the stuff.
Live yeast can break down the dye, and dead ones can’t. Live yeast, and apparently live Panaeolus, appear colorless or only faintly blue, and dead yeast appear dark blue. Some of the pictures are stained, others are not.
BTW, I emailed my vendor with the pictures, and it’s of course true, the vendor does use yeast flakes.
I had already discovered this problem before when using yeast in my agar media. Recently, I finally found an autolyzed yeast extract with only that ingredient that wasn’t expensive. Biology supply yeast extracts are expensive. It’s better because the mycelium doesn’t have to digest chitin to get to the nutrients inside the yeast, and because nobody serious anywhere uses whole yeast. Paul Stamets old books used it in agar, and it stuck with us.
It’s not showing off for me to bring up the methylene blue test. Any advanced beer brewers, wine makers? Brewers have to know not only the yeast count , but also % yeast viability, before pitching a starter.
It is also totally conceivable that people out there have 1,000X microscopes, because I’m seeing 5,000X on Amazon for $300, so I’m not showing off by saying that I use a microscope.
Surely nobody in the comments is going to demand to know why I didn’t just use agar, because yeast grow so well on it……my spawn was ready to inoculate. I wanted it then.
I’m really just looking out for the vendor, cause they’re excellent, and Reddit is full of toxic people, and I don’t want some schmuck trying to be important with his/her (but probably his) new microscope, and then badmouthing the best pan LC vendor that I know of.
And why didn’t I just say, “Bruh, I had sum contamed LC, so put it on some agar, it was clean so I sent it” ?
Because the whole comments section would fill up with people telling me all the ways that I screwed up. “Did U flame the loop and then not let it cool? Is it a fastidious yeast that couldn’t grow because ur agar is missing a nute?”
“Nah, Bruh, dat shit contamed.”
And then these people would spread the gossip far and wide, costing my vendor business.