found trivia:

In 1964 General Mills introduced its magically delicious cereal Lucky Charms, with its animated character Lucky the Leprechaun the keeper/protector of “me Lucky Charms,” from the ubiquitous kids in constant pursuit of Lucky and his cereal and the original marshmallow charms (aka marbits): pink hearts, yellow moons, orange stars, and green clovers. Now GM is introducing ... you might want to sit down ... Chocolate Lucky Charms. Yes, there have been changes in the cereal over the 40 years but not quite so dramatic as to alter the color of the remaining milk in the bowl to such a degree. Like regular Lucky Charms, the Chocolate version contains eight charms: hearts, shooting stars, horseshoes, clovers, blue moons, pots of gold, rainbows and balloons.

Over the years GM has changed its line-up of charms and introduced special holiday related charms:
1975-addition of blue diamonds
1984-addition of purple horseshoes
1989-red balloons join the line-up
1991-red balloon and orange star are
dropped in exchange for the star/balloon
combination.
1992-the rainbow (pink, yellow, blue) is added
1994-yellow moons out,
Pot O' Gold (yellow & orange) in
1995-the overall color of the charms is
intensified; the moon returns, but this
time around the moon is blue; the star
alters from six point to five points
1996-green clovers are replaced by a light
green hat with a darker green clover

Source:

CYNTHIA TURNER'S
Cynopsis: Kids!
01/31/05