A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Position-Finding
From: Chris Caswell
Date: 2017 Mar 20, 15:14 -0700
I discovered a month or so ago that some of the sextants used radium paint to illuminate the bubble for star shots-from what I can gather, it is probably Ra-226, which has a half life of around 1600 years. The sextants that I own that are hot are: the Bausch and Lombe AN5854-1 and A8-A, the Bendix AN5851-1, and the Pioneer MK IV, which is the hottest of all. I purchased a Lionel CDV-700 radiation meter, and after measuring background radiation, arranged my sextants so my working and sleeping space are at or near background. (I live in one room) If you collect these instruments, you might want to keep them away from your living spaces.
Chris in VT