Silver will not produce this type of colour and oxidation. Only nickel (or cupro-nickel) produce the oxidation color.
This coin is also known as Ringgit Janek, Ringgit Geroda, Ringgit Matahari. Yesterday, from an auction site, I found this coin and interested into getting it for my research purpose. I pay the sum of RM150.00 but only to find this coin is fake.
So, collector who has found this type of coin, please be careful. It may look authentic, and the mint may look very perfect. At one glance, it looks to be genuine, but after looking at it thoroughly, it doesn't take long for me to differentiate it as fake coin. It is not silver, but I assume it is cupro-nickel. The details look very perfect, to which the coin of this year should have wore somewhere - but this coin does not have any trace of wearing.
I have to return it to the seller, I am not saying the seller is selling fake coin, but his/her source maybe selling to him/her this fake coin.
I would say, please be careful to everyone because spending money, a serious big money on something not worth it, is SO SUCH A WASTE.