A note about identifying these tiny mint marks: Sometimes the mint marks
are very clear and easy to see. Other times they are quite subtle and difficult
to pick out. The incuse "C" can appear as a tiny circle. The incuse
"B" can also be indistinct. The raised "B" is particularly
prone to problems due to wear, damage or poor striking. It often appears as a
little bump on the coin. Great care must be taken to identify some mint marks.
It often helps to use a magnifier and to use strong directional lighting. An
invisible mint mark can often be quite clear with the proper choice of
lighting.
The following mint marks are illustrated by
photos below:
Incuse "C"
Incuse "B"
Raised "B"
Dot mint mark
Narrow and Coarse Milling, different diameters
1. Incuse "C"
Detail of Incuse "C"
(Note white arrow pointing to the incuse "C")
2. Incuse "B"
Detail of Incuse
"B"
3. Raised "B"
Detail of Raised "B"
4. Dot mint mark (1874, 1877-1883)
Detail of Dot mint mark
The single dot is below the center of the
date just above the ornate.
5. Narrow and Coarse
Milling, different diameters (1862-1876)
The 1/4-Rupees minted in Calcutta 1862-1878
have no mint mark.
They have a diameter of 19.3-19.4mm and have a coarse milling.
The 1/4-Rupees minted in Bombay 1862 and 1875-1876
have no mint mark.
They have a diameter of 19.7-19.8mm and have a narrow milling.
The 1/4-Rupees minted in Madras (minted only in 1862)
have no mint mark.
They have a diameter of 19.9-20.0mm and have a coarse milling.
It is useful to have a caliper to measure these small
differences in diameter. However, as can be seen in the photo at the right, it
is possible to compare two coins and detect a difference in diameters. Using
the fact that the middle sized coin of the three possibilities has narrow
milling and the smaller and larger diameter coins have coarse milling, it
should be possible to identify the coins if you have at least two different
types. Look at the top of the photo and you will see a very definite difference
in coin diameters.
Calcutta (diameter 19.3mm, coarse milling) is on the
left.
Bombay mint (19.8mm, narrow milling) is on the right.
Example of Madras mint is not available here.
