Zoisite

Manga: Zoisite (Zoicite) is the third of Queen Beryl's generals. Zoisite is also known as the commander of Europe. Zoisite at one point disguises himself as a woman in an effort to find the ginzuishou. As a woman he is known as Professor Izono. He appears on televeision and encourages the people to look for the ginzuishou and tells them it has the power of eternal youth. Later after not finding the ginzuishou, Zoisite collects energy from humans and later confraonts Sailor Moon. In his last scene, Zoisite traps Sailor Moon and demands the ginzuishou. When he is about to stab her, a boomerang thrown by Sailor Venus knocks his knife out of his hand and then a second boomerang slices his body into pieces.
Anime: In the Anime, Zoisite is still the third general. Zoisite is also responsible for killing Nephrite. Queen Beryl summons him to find the seven nijizuishou (or in the n/a dub, rainbow crystals). In the original japanese anime Kunzite (the fourth general) is Zoisite's lover and teacher. In the N/A dub, Zoicite magically became female and Zoicite and Kunzite still had their "potential" love for each other. I say potential because Zoisite is later killed by Queen Beryl, after attacking Tuxedo Kamen (whom Beryl has fallen in love with).
Name origin: Zoisite (the correct spelling) is an ornamental gem or stone. The mineral is often gray, brown, green, and blue. A popular variety of zoisite is Tanzanite, a blueish gemstone.