K.U.K HOF-U. KAMMER- JUWELIER U. GOLDSCHMIED
A.E.KÖCHERT
SEIT 1814
October 21st 2025
Results of the examination of the ‘Florentine Diamond’,
The ‘Florentine Diamond’ is loose, which means that it was removed from its setting at some point in the past. The hat pin in which it was set has been preserved in four fragments: first, its setting, into which the stone fits exactly, and then three separate parts with old-cut diamonds. When assembled, these four parts correspond exactly to the historical photograph of the hat pin with the ‘Florentine Diamond’.
Its weight was determined to be 137.17 carats using a mobile carat scale (with a possible deviation of up to 0.02 ct) – this corresponds approximately to historical sources, which provide slightly varying information: 133 ct (Kathrin Unterreiner, ‘Habsburgs Verschollene Schätze’ [The Lost Treasures of the Habsburgs]) and 137.2 ct (Wikipedia).
The fact that the ‘Florentine’ is a diamond was confirmed with the aid of an electronic diamond tester. This measures the authenticity of a diamond based on its thermal conductivity.
Its cut pattern corresponds almost exactly to representations in historical sources.
All of this gives me certainty that this is the genuine, historical ‘Florentine Diamond’.
Here is a summary of the factors that led me to this conclusion:
1. The stone fits into its setting.
2. Its weight of 137.17 ct corresponds to historical sources.
3. Its authenticity as a diamond was confirmed by an appropriate electronic device. 4. Its cut corresponds to historical sources.
Grafalet
Christoph Kochen
A.E. Köchert
Neuer Markt 15 1010 Wien
(43-1) 512 58 23
www.koechert.com
A.E. Köchert Alter Markt 15.5020 Salzburg
(43-662) 84 33 98
