The Hello Kitty Charms measure 3/4" (19mm) wide and 1/2" (13mm) tall. The flowers are a red stone with a darker red stone in the center on the earrings and a pink stone in the center of the Pendant Charm. The Drop Earrings are on hooks. There is no material listed, so the types of stones or metal are unknown. 

These Vintage Hello Kitty Drop Earrings are pre-owned but unused. They are in excellent condition. They are very sparkly. It is hard to photograph because they are very reflective, but they are in great condition. (The actual color of the clear stones are similar to Cubic Zirconia and the metal is similar to silver)

(The dime in the image is used for comparison only and is not included.)