Seychelles: 10 rupees 2016 versus 2018 [solved]

https://en.numista.com/catalogue/pieces99677.html

the 2016 weighs in at 7.05 grams
the 2018 weighs in at 7.71 grams

I weighed both several times, but those weights are correct!

All other measures are the same....

That's around 10% difference, which is far too much, how do you incorporate that in the catalog?

Ole

I have both years, I will weigh the this evening and let you know. I learn the metal-composition is different.
I will also do a XRF-test on them and let you know.

The difference really exists. The change in coin's composition in 2018 occurred due to rust on coins dated 2016.
Brass plated ring was replaced by nickel-brass by decision of Royal mint and CBS.
See details here
BTW, mintage of new coins in 2018 is reported to be 5 mln. pieces

In earlier article CBS representative gave info about mintage of 2016
Was ordered 2 mln. pieces
Was produced 1 mln. pieces
Placed into circulation 6 000 pieces
See here

I have got an example of the 2016 10 Rupees in my collection, but not the 2018 one though.

Aidan.

Based on provided info, this cointype should be Splited into 2 types.

I don't know if I should report change from coin's form or referees read this forum and can do it without my notice.