what metals are singapore coins made of

[MacBrandon]

The provided context from the Monetary Authority of Singapore website was inaccessible, showing only maintenance or error messages. Therefore, the following information is based on general knowledge regarding Singapore's currency.

The composition of Singapore's coins varies depending on the denomination and the series of issuance. The current Third Series of coins, which was introduced in 2013, utilizes a multi-ply plated steel technology for enhanced security and to differentiate between denominations by electromagnetic signature.

In this current series, the one-dollar coin is bi-metallic, consisting of a brass-plated steel outer ring and a nickel-plated steel inner core. The fifty-cent, twenty-cent, and ten-cent coins are all manufactured from nickel-plated steel. The five-cent coin is composed of brass-plated steel.

Prior to this, the Second Series, known as the Floral Series, used different alloys. The one-dollar coin and five-cent coin were made from an aluminium-bronze alloy. The fifty-cent, twenty-cent, and ten-cent coins were made of a cupro-nickel alloy, which is a combination of copper and nickel. The one-cent coin, which is no longer in circulation, was composed of bronze.