Can anyone explain some interesting images from rosemery petal through cross polaroids?

[billben74]

Hello all.
I fixed some rosemary petals in FAA washed them in distilled water (x3) stained with saffarin o (for about a minute fairly light staining) and then dehydrated through 25,50,75,100 IPA then mounted in Euparal.

Through crossed polarioids I got some interesting images. I presume crystals of something. They all at x200 (I think I was really just snapping)
This is the sort of thing I saw through normal brightfield

14_02_201622_44_510048RosemaryPetalSmall.jpg (52.16 KiB) Viewed 3009 times

I thought the xylem vessels might be interesting through crossed polaroids so followed them and saw:

14_02_201622_54_280062RosemaryPetalXylemCrossPolaroids.jpg (70.6 KiB) Viewed 3009 times

You can see the xylem vessel. I was fairly amazed.

I also saw

14_02_201623_10_130099RosemaryPetalx200CrossedPolaroids.jpg (68.18 KiB) Viewed 3009 times

I am constantly amazed by the beauty I see down my microscope and I find crossed polaroids can produce some of the most stunning images.

I'm a science teacher but supply the photography teacher with images which she uses in her lessons.
I also drop some of my pics into my lessons either because I'm trying to demonstrate some science (e.g. paramecium video with contrile vacuole in lesson on osmosis) or when the lesson's work is done just to make the kids like their science lessons.
Normally I know what I'm seeing. I haven't really got a clue here.
Anyone help?

[billben74]

Sorry, the 7 was meant to be a question mark

[gekko]

billben, a very good start. I also liked the colorful polarized light images, but the brighfield one was also good. Sorry, I cannot tell you exactly what we are seeing and hopefully some knowledgeable forum member will chip in.

[75RR]

Can't help with the ID either, just wanted to mention that it is possible to edit a post - you can swop that 7 for a ? if you want.

[zzffnn]

I read somewhere previously that many polymer fibers produce colors under crossed polarizers. Xylem can be considered as polymer fiber, right? Color may depends on thickness and degrees of polymerization, so fiber may not always produce color under X pol.

[billben74]

Thanks all.
The xylem are the red circles/tube type thing running down the centre of the image of the second image. So yes they are rotating the light. But I don't think the the crystaline colour explosion (or whatever it is) is xylem. Maybe its saffarin o. Does anyone know if saffarin o shows birefringence?

[zzffnn]

Many crystals do. So it could be.