Mineral grains
Mineral grains
There is a DIY tutorial online for a technique involving glueing a crystal grain to a needle and rotating it under polarised light. Does anyone know what this technique is called or even better, the tutorial I am looking for?
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Re: Mineral grains
Haven't seen that tutorial but have seen several others concerning the use of petrographic microscopy, have a petrographic scope and have studied. Rotating a mineral grain or thin section under extinct polarized light and using certain filters is the major means of mineral identification. Look on YouTube. Subject is " Optical Mineralogy. "
Enjoy. Greg
Enjoy. Greg
Re: Mineral grains
The rotating needle, may be called the "spindle stage".
Re: Mineral grains
Thanks Patta. Thats what I was trying to recall.
For those unfamiliar, this system help. Someone shows how to make a home made one.
https://youtu.be/j955_cOi_qE
For those unfamiliar, this system help. Someone shows how to make a home made one.
https://youtu.be/j955_cOi_qE
Re: Mineral grains
An extremely crude but effective implementation, to hold and rotate insects:
https://www.photomacrography.net/forum ... =43787
https://www.photomacrography.net/forum ... =43787
Re: Mineral grains
Decades ago, gluing a crystal to a rotating needle, such that its orientation in space was reproducible and defined along one of the crystal axes, was a standard technique of crystallography. The needle was mounted with plasticine (or similar stuff) to a simple goniometer head. Crystals were glued with shellac for example. Such operation was best done under viewing with a stereoscope (say, 0.7X-1X).