Seventeen Radiolarian Shells, Barbados (pleurax mt)

For the readers who are not familiar with the subject : these are the fossil shells of radiolarians, microorganisms that mostly live in the warmer seas and oceans and resemble sun-animalcules (heliozoa). The shells or microscopic “glass houses” they’re in have ever since their discovery in the 19th century, been very attractive to microscopists.
This post covers one of the storage slides I received recently, containing cleaned material found in calceous rock material on Mount Hillaby, Barbados.
I’ve used this for making strew slides with a random selection of different shapes. Observation method no.1 was brightfield combined with polarisation and use of the 50x/1,0 Leitz oil immersion objective. Besides that also colour DIC was used in a number of images. Mountant of choice was pleurax which I started using a couple of months ago for (attempted) diatom slides. The high refractive index (1,70) combined with the oil immersion provide a closer, more detailed look and gives an idea about their 3-dimensional shape.