Large grey-brown semi-transparent Phosgenite crystals emerge from the galena matrix.
Sample of very low visual impact in daylight due to the fractured and mostly wrapped into the dark matrix cristals.
On the other hand, the fluorescence is very bright.
In LW the crystals show a greenish-yellow sheen of non-uniform intensity. This gives character and depth, making the piece non-trivial.
In Mw, markedly different luminosities and tones are perceived among the crystals.
In shortwave, however, the response is much less and not worthy of note.
Dimensions and weight: 6.5 x 5.7 x 3.6cm; 310g
Origin: Monteponi mine, Iglesias, SU Sardinia, Italy
(Photo and collection by Stefano Buzzoni)
The dark matrix is mostly galena in massive form....
LW exposure: 3 x BLB Philips PL-S 9W/4P BLB (356nm)
Mw exposure: 3 x UVB Philips PL-S 9W/01 G23 (311nm)