Grade 509, 21 diamond, ruby and sapphire jewels adjusted 5 positions, manufactured from 1911 to 1920 a total of 3,077 movements in 21 runs make up this grade. Model 4 size 12/14 open faced; bridge movements of high quality, double roller and patent micrometric regulator.
Observations, Most movements have a broad striped pattern demaskeening with the majority named Hallmark; Ariston, Ariston rated, Illinois and Illinois Watch Co. make up the remainder. Precise have a spiral etched pattern. The size 12/14 movements have a size 12 bridges and size 14 pillar plate and have a stretched enamel dials that are not recessed into the pillar plate, they require special cases and were cased at the factory. Hallmark watch were made for United Jewellers, marked The Hallmark Watch on the cuvette. Ariston and Ariston rated watches were made for Marshall Field & Co. Chicago, have Ariston marked cases with the M F & Co logo. The Illinois watches were advertised as part of "The Springfield Watch" series and have this on the cuvette. I,m unsure if the Illinois Watch Co. models come under The Springfield Watch.
Variants, Two types of escapement bridge can be found, the majority have the two fingered bridge, Ariston models have a full plate bridge.
Description, 21 extra quality diamond, ruby and sapphire jewels; gold settings; accurately adjusted to temperature, 5 positions and isochronism; very carefully timed; compensating balance having gold screws; steel escape wheel; double roller escapement; red ruby roller and pallet jewels; jeweled barrel; best quality Breguet hairspring, Phillipe coil; patent micrometric screw regulator and first quality mainspring; unusually large dial is a special feature of the watch, all were factory cased.