Lt.Col Baring c1969, who was a DY Officer prior to amalgamation with the LY PAO, (pictured as a Major above c1965) shows the detail in the DY Yeomanry Mess jacket & Waistcoat. The DY mess kit above has been date as early as 1930 and was most likely to have been worn post 1920. The LDYPAO regiment wore the same mess kit with the change to "silver" lace instead of gold.

The DY mess kit post World War 1 changes again to the above example.

In 1906 an "adopted" mess kit was chosen, this was decided by RHQ DY on the 23rd February in that year. The new mess jacket was army blue with scarlet cuffs and roll collar, edged all around with gold Russia braid, and with twisted gold shoulder cords. It had gilt and silver collar badges, a smaller version of the cap badge, and was worn with a white Marcella waistcoat. The overalls had gold stripes, this changed in 1908 to have double stripes of scarlet cloth.

The above mess kit appeared in 1894, a dark blue jacket with scarlet facings and gold oak-leaf lace, which was worn with a new scarlet vest with six loops of chain gimp on the front, as for the 6th Dragoon Guards.

DYC Captain c1895
The Derbyshire Yeomanry Cavalry also wore a Dragoon pattern "Astrakhan" patrol jacket (pictured above) from c1884, this stopped for the other ranks around 1900. The Officers still wore theirs as an alternative jacket for Mess Dress. Its unclear when this practice stopped. Astrakhan fur comes from the Persian Black sheep and is used for its tight warm black fur (often seen on Russian Cossack hats).

From 1864 a relatively plain stable jacket and scarlet vest was adopted by the regiment. The blue jacket had scarlet facings but only the top of the collar and pointed cuffs were edged with gold oak-leaf lace. The body of the garment and neck seam were edged with a gold Russia braid and the front fastened with ten small gilt buttons. The vest had no collar and was also fastened with ten buttons. It was edged in plain Russia braid  and so too were the pocket slits which had trefoils and each end.