MILA’S MOMMY RING: Mila Kunis isn’t only a mom now, she’s also a jewelry designer — of sorts. Prior to giving birth to daughter Wyatt Isabelle in early October, the actress — together with Gemfields, for which she is an ambassador, and jewelry brand Marina B — designed an emerald ring to celebrate motherhood. “While we created it for Mila in celebration of Wyatt’s arrival, this is the kind of ring any woman can wear,” said Paul Lubetsky, chief executive officer of Marina B. Well, any woman with a certain budget: The ring, made of 18-karat yellow gold and featuring a Gemfields Zambian emerald, retails for $4,800 and is available by special order through Marina B’s Web site. But the actress and the companies are putting the revenues to good use: 100 percent of sales profits will be donated to Gemfields Nkana Health Center in Zambia, where the Gemfields mine is located, to support the addition of a maternity clinic.