the young bearded gentleman naturalisitically modelled attired in a slashed tunic and raised on a socle,

The original sculpture from which this bust is cast is modelled as a half-length figure holding a cap in his right hand and with his left hand on his hip ( V&A Museum number 7623-1861).   The catalogue entry for this figure at the V&A comments that,

"The figure does not fall into any of the normal classes of portrait. Its free and frankly naturalistic modelling and its cutting at the level of the hips make it improbable as a preliminary model for a funeral statue in bronze or marble. It may have been made as part of one of the frequent but ephemeral festival decorations that were produced during the Renaissance. The costume suggests a date of about 1540."  

In Maclagan and Longhurst "Catalogue of Italian Sculpture", 1932, VAM, p.139 and illustrated Vol II, pl110, it is noted that the style of the bust has previously been compared with that of Angelo Bronzino that it has been tentatively ascribed to Domenico Poggini.  

This is the first time that the beautiful piece-mould created by Domenico Brucciani's workshops in Goswell Road has been used to cast this bust of of an unknown sitter in probably over 100years. The results that they were able to achieve from their hand made moulds are evident from this cast in its capturing of the fine detailing and undercuts of the original. Brucciani’s had been commissioned to make a mould by South Kensington Museum (as the V&A was then known) after their acquisition of the 16th Florentine stucco figure from the Gigli-Campana collection, in 1861. It is likely that they did not make the cast until shortly after 1865 when Henry Cole accompanied by Prince Albert, had pushed for the Europe-wide advancement of Cast Courts at the Paris Exposition of that year, and casting of great works took on a new impetus.