Description - PM type 12 (JC-MN) singular diamond with bars varying in size, thickness of bars, and spacing, parallel to the short diagonal. The key aspect of this main type is a letter C combined with numeral inset.

This entire PM group (including subtypes without letters) in use Madras postal sub-region, between 1868-1874, although Cooper notes a stray instance dating to 1877. Martin records the earliest instance as 2nd August 1866 (an instance found in this collection!), and a reasonable number of other PO numbers. All examples are scarce. A few very scarce examples are found with blue ink. Overall many examples of the PM group, with a wide range of PO numbers are found on covers or as single stamps. 

Examples found in this collection date between 2nd August 1866 (149 Nagore) to 3rd September 1875 (5 inverted!)

PM subtype 12a – (JC) smaller diamond with thicker bars numeral inset only. Considered scarce.

Examples in this collection date between 2nd June 1868 to 8th May 1873

PM subtype 12b – (JC) larger diamond usually finer bars spaced apart numeral inset only. Considered scarce.

Madras ‘1’ instance 23rd November 1878 – later than latest recorded by Cooper

PM subtype 12c – (JC) varying sized diamond without letter distinguishing feature well-defined numeral inset almost appearing like a box. Considered scarce. 

An example cover in this collection ‘’3 dates to 5th October 1866 up until 5th July 1873

PM subtype 12d – (JC) varying sized diamond, and bar thickness, key feature bars are parallel to short diagonal without letter nor numeral inset, not to be confused with the similar PM type 33 (JC) - A few instances are found on lithograph issues. Considered very scarce. 

Example French Rocks dates 21st March 1868

PM subtype 12e – (JC) large diamond thicker bars spaced apart large numerals 6mm high. Considered very scarce.

Violet-blue example 1872 another 26th February 1872 – In black 9th September 1873