"D" denarius, RRC 171/1, Uncertain Mint

Denomination: Denarius
Era: C. 199-170 BC
Metal:  AR
Obverse: Helmeted head of Roma R,;  X behind. Border of dots
Reverse:  Dioscuri on horseback right, each holding spear, star above each head; "D" below; ROMA in  2 line frame.   
Mint: Uncertain
Weight: 4.75 g
Reference: RRC 171/1
Provenance:  Soler y Llach, Auction May 6, 2021, lot 260  

The D symbol is generally believed to be either a mint mark or a moneyer's initial but it is impossible to determine which, who the moneyer might have been, or where the mint was.  Grueber suggests because the style is similar to the QLC and VAR issues, that this might be an engraver's initial.   I see little similarity in the style of these issues which were cataloged adjacent in BMCRR, but RRC places the D issue years later.  Grueber notes that the denarii of this issue are of "rude fabric" and not the work of the Rome mint.  The dies are the work of at least two engravers, the large D engraver and the small D engraver.  Each of which have their own distinct style. This example is the small D engraver and in my view, the more elegant of the two.  The issue is quite scarce.  The Schaefer Roman Republican Die Study suggests perhaps more small D dies than large D dies.

Rare in higher grades.  Exceptional style for the issue. Lovely light toning possibly the finest known and EF.   

Sammlung : Symbols -Early anonymous Roman silver coins with symbols and Mintmarks