Cleaned likely with a material called Silvio, which is a silver polish, failing that a jewellery whizzing bath thing sold by dealers.
The coin itself would barely grade fine, the king has an incomplete crown band.
Coin is worth bullion value only because of it, which is around $1.60 in New Zealand money.
You can see the scratches from cleaning and the blackened rims, meaning it was a very low grade cleaning job, probably with silvio and a harsh metal cloth.
Please avoid.