  Yellow Pyroxene.  
Description from the source: 
A very rare "yellow" Pyroxene (probably an Aegyrine/Augite, Vesuvio, Napoli, Italia), with a incredible intense yellow color, associated with reddish Olivine and black Spinell. An extremely good Vesuvious specimen for the collectors. 4x2,5x2 cm; 22 g. 
Source: Simone Citon 
Contributor: John Gray 
Acquired: 30 September, 2008 
Text Updated: 1 October, 2008 
Price: Trade 
Size: 1.6" 
Composition: CaMg(Si2O6)
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