Woodstock — Gemologist Jeffrey Zayas plans to open a retail jewelry store this week on Central Street in the former Elliott Newman Jewelers location. Zayas, who lives in Woodstock, is a native Vermonter with nearly 20 years of experience in the jewelry business, gained from working in stores in New York City and Vermont. He’s a graduate of the Gemological Institute of America, in Santa Monica, Calif., and is trained in diamond and colored-stone grading and gem identification. He also received graduate certification from the Gemological Institute in New York City. The store, Zayas first retail operation, will offer estate, vintage and contemporary jewelry, appraisals and will buy gold and silver, Zayas said in a …