One of a Kind AO-GIA Gem Instruments Cat #480 110v Beck Spectroscope Table Top

Description

American Optics - GIA Gem Instruments Cat No. 480 110V Beck Spectroscope table top unit.
Comes with plastic cover, stone holder, extra light bulb, original sales receipt.
Copy of The Spectroscope and Typical Absorption Spectra from Dick Liddicoats Handbook of Gem Indentification.
The original The Gem Spectroscope Unit Operation care, cleaning and Maintenance for this unit.
OPL Student’s Guide to Spectroscopy by Colin H Winter FGA, DGA.
Includes a one of a kind set up invented by Charles L. Wells Jr. ICGA in the late 70’s. (Only 2 made, this is the only survivor)
Adjustable custom brackets holds a Pyrex glass container filled with copper sulfate, that mutes the hue, tone, and intensity of green, yellow, orange and red colors in the upper part of the spectrum, allowing for a consistant clearer view in the blue lower part of the spectrum for the 4155 cape line in yellow diamonds.
I have taken 8 GIA-AGS master diamonds and recreated the intensity of these 4155 cape lines (both transmitted, and table up and table down)
on a graph paper (the originals will be included in this sale.
This was an invaluable resource for me when color grading mounted cape series diamonds having done hundreds of appraisals using this method.
The diaphragm became non-functional years ago. Replaced with a black piece of cardboard that I put a hole in the middle and has worked fine for me for many years.
I am including a custom lighted aluminum canister with adjustable dark field illumination and fully functional diaphragm that you could transfer to the spectroscope. I would leave it alone and keep the other piece of equipment. Extra stone holder is also included.
Also throwing in the Journal of Gemmology dated April 1983, that includes a great article on the recognition of the new synthetic rubies that includes 41 pictures of synthetic rubies by Dr. E. J. Gubelin C.G. F.G.A.
One owner Bill Berthet retired CGA-FGA.  Well cared for, used in my AGS accredited Gem lab at Berthet Jewelers in Jacksonville, Florida