Considering illustrative sources of period artwork, the very same type of rapier featuring a plum-shaped pommel was part of the equipment of a caliverman of c. 1600 as well - a colored engraving from Jacob de Gheyn's
Wapenhandelinghe (1608) attached.
For more information on characteristic caliverman's equipment of ca. 1600 to early-17th c. please see
http://www.vikingsword.com/vb/showth...rman%27s+flask
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