Excellent series!

Dave

iconoclastica wrote: ↑

Mon Sep 14, 2020 9:46 am

I think is part of the skeleton of a sea-star, in Dorset probably Asterias rubens.

Wim

Thanks for that Wim, I just found another one, I don’t think I would have ever worked that out!

Dave

I've already sent some samples off to a lab but I thought I'd try to see if I could detect any possible hyphal remains in these samples. Chitin, a constituent of the walls of fungal hyphae, fluoresces white under UV when stained with Calcofluor White. I have some Calcofluor White so I stained a samp...

The last photo was taken using a 100x NeoSPlan objective, and are “tunnels” in to a thin flake. The view is looking through the transparent flake so the tunnels are coming towards you from the far external plane. The flake is probably under 60 microns thick and the tunnels are under 5 microns wide. ...

Beautifully photographed!

Dave

Here are some more images. There are larger versions in a flickr album here https://flic.kr/s/aHsmQGjVkj . 10x Obj. Polarised mica_874.jpg 10x Obj. mica_bw.jpg 20x Obj. mica_redriuh.jpg 50x Obj. mica_95945.jpg 50x Obj. Stereo mica_stereo_55-Edit.jpg Suspiciously fungal looking. This is coming toward...

I have been contacted by a scientist I sent the photos to and he has said that they may have been produced by hyphal fungi rather than bacteria; I’m going to post a few flakes to him so that he can look at them on a micro CT scanner. Meanwhile I’m going to take some more photos.

Dave

Hi Lou,

the second photo is full frame with a 20x objective.

Dave

Count me in with the "Beautiful photos!" I suppose it's a silly question, but has biological origin of the curved needle inclusions been ruled out? Knowing nothing about those cases, it's easy for me to imagine biological burrows getting re-filled with deposits of a different mineral. --Rik Thanks ...

Thanks for the comments. Beautiful photos! That said I wouldn't discount these being inclusions of another mineral. I have seen this kind of shape in curved needle inclusions in other minerals. There has been a suggestion of bacterial etching in garnets before but it's been met with a lot of skeptic...

Hi Pau, I’d seen these bacteria tracks in ooids https://www.photomacrography.net/forum/viewtopic.php?f=14&t=36436&hilit=Oolite but they are calcium carbonate, as are the mollusc shells they also tunnel in to. Maybe they like the iron content of the mica but silicates are harder to dissolve than carb...

I took a small sand sample from a beach in Dorset, UK the other day. It's mostly quartz grain sand and I was hoping to find some foraminifera, I did but I also found that there were lots of phyllosilicate (mica) flakes in the sample. The flakes were up to 3mm long and varied in thickness, they looke...

Welcome!

Excellent detail and lighting.

Dave

Very nice set. I had no idea what I. echinospora was - it’s the Spiny-Spored Quillwort! Great name and interesting plant. I see it produces much smaller microspores too.

Dave

Excellent!

Dave