Passover Seder plate, a ceremonial dish used during the Jewish holiday of Passover (Pesach).
It is made from molded art glass in a deep amethyst or purple hue. The center features a prominent textured Star of David (Magen David). The plate is designed with six circular depressions surrounding the center.  Each of these indents holds one of the six traditional symbolic foods of the Seder:
Zeroah (Shank bone)
Beitzah (Egg)
Maror (Bitter herbs)
Chazeret (Second bitter herb)
Charoset (Fruit, nut, and wine paste)
Karpas (Vegetable, usually parsley)
Approximately 11 1/4” in diameter and hefty 6 pounds and 12 ounces in weight. 
Excellent vintage condition.