SRI LANKA - Five Rupee
A definitive decimal currency Five Rupee brass plated Steel coin with a milled edge with incuse letters. There was no Press notice from CBSL on this issue from the Royal Mint made after the 2013 March contract to Mint of Finland Ltd. was cancelled. This coin was found in Circulation on 2014 June 18th. According to CBSL the coins arrived in island in 2014 May (needs confirmation).
Obverse : The Armorial Ensign of Sri Lanka
Reverse : The large numeral 5 at the centre with FIVE RUPEE in Sinhala, Tamil and English superimposed. Sri Lanka in Sinhala appear at the apex and Tamil and English on each side. The year of issue at the bottom. The coin is 2.7 MM thick and has incused lettering C.B.S.L. on edge in Sinhala, Tamil and English.
Issued in the Royal Mint Plastic bags of 1000 coins. mint coins. Printed in Black on pack is SRI LANKA / 5 RUPEE / 1000 Pieces.
In 2013 March, Finland was awarded a contract by CBSL to mint 100 Million Rs5 coins over the next 3 years. This order was cancelled by CBSL without any announcement. Reasons Unknown. I suspect it could be the edge lettering on this Rs5 Coin.
In 2014 June, I found one in circulation, before it had been reported to me by anyone.
The Brass plating appears to be much brighter almost gold-like.
The grooves on the edge of the coin are less sharp. The edge lettering is clearly poorer. Most are not in middle of edge but to the edge.
I thank Kushan Wijayapala and Palinda Jayasinghe of Commercial Bank for getting me Mint 2013 Rs5 coins on 2014 June 25 for analysis. This also revealed to me that the coins were minted at Royal Mint and not in Finland as expected.
The coin was scaned at 600 dpi and the images are displayed at 300 dpi.
Inspection of these 100 coins under 10x magnification showed no significat defects other than typical bag marks.
Weighing each of the 100 coins on a digital pocket scale with a precision of 0.01 grams, I found that the coins weighed between 7.54 amd 7.86 (±2%) with a mean of 7.73 grams. The distribution had a rms dispersion of 0.048 (0.41% of mean weight). It had a negative skewness of -1.11 and was leptokuratic with a positive excess kurtosis of +3.6. i.e. distribution more peaked than normal.
It appears that coins have not been removed by some weight control. This is unlike the Slovak and Royal Dutch Mint which appears to have clipped both lower and higher of a weight range.