fossil diatoms

Frank Fox · Post by **Frank Fox** » Thu Sep 01, 2011 4:09 am

Hello,
today I will show you photos of fossil diatoms from Palos Verdes.

RogelioMoreno · Post by **RogelioMoreno** » Thu Sep 01, 2011 3:08 pm

Beautiful!

Rogelio

Cactusdave · Post by **Cactusdave** » Fri Sep 02, 2011 12:17 am

Very nice images, I love diatoms, especially the truly bizarre fossil forms. Information on your choice of lenses and method of lighting would be welcome.

Mitch640 · Post by **Mitch640** » Sat Sep 03, 2011 8:13 am

Beautiful images and where do you find fossil diatoms?

Cactusdave · Post by **Cactusdave** » Sat Sep 03, 2011 12:22 pm

Mitch, fossil diatoms are found in deposits called diatomaceous earth, or diatomite. They can be cleaned and mounted for the microscope, though it is quite a laborious process. Mounted fossil diatoms were a favourite subject of the Victorian microscopists, and there are many people who are still very interested in them. A few even keeping the old skill alive of mounting individual diatoms in complex and pleasing patterns as well as in type groups from different localities. There is lots of information from a fellow enthusiast based in the US here http://micrap.selfip.com:81/micrapp/samples.htm

Mitch640 · Post by **Mitch640** » Sat Sep 03, 2011 12:29 pm

Dave, I have read about the cleaning process and I have seen a number of images and articles about those "art" slides. Not sure I have the patience for it myself. Where did you get your samples?

It just occurred to me, are these all the same diatom, just at different focus levels?

Cactusdave · Post by **Cactusdave** » Sat Sep 03, 2011 2:27 pm

As these are Frank's pictures, I'm sure he'll give you more details on how he took them and where the slide came from. My own personal selection came mainly from Ebay and from Klaus Kemp http://www.diatoms.co.uk/ .

Frank Fox · Post by **Frank Fox** » Mon Sep 05, 2011 6:03 am

Thank you.
The diatom were on a strew slide.
I've used a Zeiss Jena lens CF250 PlanApo 100x.
Lighting was bright field.

Marek Mis · Post by **Marek Mis** » Mon Sep 05, 2011 8:49 am

Hello Frank,

Beautiful images.
Two first ones slightly look like in phase contrast.

Marek