My experience is that sirius red F3B does give green birefringence with
polarisers.  However, the colour is noticeably darker than the green with
congo red.

Bryan Llewellyn

-----Original Message-----
From: angelrj@email.uc.edu <angelrj@email.uc.edu>
To: histonet@pathology.swmed.edu <histonet@pathology.swmed.edu>
Date: March 12, 1999 11:40 AM
Subject: Sirius Red


>We have had several requests lately for Sirius Red.  We normally use the
>Congo Red technique.  My question is:  Is there supposed to be the green
>birefringence staining with the Sirius Red?  I've checked all my
>resources.  It is not mentioned in the few procedures I found and one
>book was contradictory.  I assume it is not supposed to since the
>sections are cut thinner (at 4-6 m.), and the majority of the procedures
>didn't mention it.  I just want to ask others who are more experienced
>to make sure I have the facts.
>
>We do have a polarizer and there wasn't any birefringence even though
>the control had dark pink areas.
>
>Thanks for your help.
>
>Rita
>
>