Hong Kong, 1989 AD., Elizabeth II, 10 Cents, KM 55.

Hong Kong, Elizabeth II, engraver: Raphael David Maklouf, Royal Mint, 1989 AD.,
10 Cents (ø 17,6 mm / 1,84 g), nickel-brass (54-63% Copper, 36-27% Zinc, 10% Nickel), 1,85 g. theor. mint weight, mintage 40.000.000 , axis medal alignment ↑↑ (0°), plain edge,
Obv.: QUEEN ELIZABETH THE SECOND , her crowned bust facing right (3rd portrait).
Rev.: HONG 香 KONG / 毫 10 一 / 1989 / TEN 港 CENTS , English legend around central beaded circle containing Chinese legend (colony name, top 香 , at bottom 港 (fragrant harbour), value flanking, left: 毫 (Hou), right: 一 (1) .
KM 55 ; Schön 4.

Year / Mintage
1985 34,016,000
1986 40,000,000
1987
1988 30,000,000
1988 20,000 Proof
1989 40,000,000
1990
1991
1992 24,000,000

The ten-cent coin is the lowest-denomination circulating coin of the Hong Kong dollar. With a diameter of 17.5 mm and a mass of 1.85 g it is also the smallest in size and weight. It is the oldest coin denomination to still be in circulation in Hong Kong. Since its first issue in 1863, there has only been one period (1942–1947) where the coin was not in use.

More on https://en.wikipedia.org/wiki/Hong_Kong_ten-cent_coin