GCAL Experts

Donald A. Palmieri Donald A. Palmieri
President, Gem Certification and Assurance Lab (GCAL)
Master Gemologist Appraiser®


Expertise: Diamonds and Colored Gemstones.
Other Areas: Antique and Period Jewelry.

Don Palmieri, a 1971 graduate in residence of the Gemological Institute of America, Santa Monica, CA and a decorated Vietnam Veteran, has been under contract with national and international government and law enforcement agencies as a consultant, appraiser, mediator and forensic expert witness. His expertise is frequently sought by museums, insurance companies, the jewelry trade, law and accounting firms and individuals. A court-appointed Chapter 11 Trustee and member of the National Forensic Center, Mr. Palmieri has been called upon to testify as an expert witness in major court cases throughout the United States and abroad.

Palmieri has been interviewed for The Wall Street Journal, Consumer Reports, Barron's, Money Magazine, The Straight Times and others. As a consumer advocate and expert in the evaluation of diamonds and gemstones, he makes frequent appearances on national and local television shows and radio programs. He also lectures at trade shows, appraisal conferences, museums, and professional group meetings.

In addition to his Graduate Gemologist (GIA) degree, Palmieri holds a Senior Member, Master Gemologist Appraiser® designation with the American Society of Appraisers. He's been on staff as a Research Associate with the Carnegie Museum of Natural History, Earth Sciences division since 1983 and taught consumer education classes in gemology, gem sciences and jewelry for the Carnegie Museum's Education Division from 1986-1999.
Maria Mrozek Maria Mrozek
Senior Gemologist, Gem Certification and Assurance Lab (GCAL)

Expertise: Diamonds.
Other Areas: Diamond Rough.

Maria Mrozek gained invaluable experience during her nine-year tenure at the Gemological Institute of America's Gem Trade Laboratory (GTL), where she earned the position of Senior Quality Assurance Diamond Grader. Maria has utilized her keen gemological skills when working with diamond cutters and manufacturers to improve the quality of rough and polished diamonds. Before joining the GCAL team, she worked with important diamond wholesalers and fine jewelry manufacturers in New York City. Maria holds a Graduate Gemologist Diploma from the Gemological Institute of America in Carlsbad, CA, as well as GIA's Graduate Pearls Diploma. Maria's expertise in quality control and quality assurance, in addition to her excellent diamond grading abilities, uniquely equip her to perform the duties of Senior Gemologist.
Lioudmila Tretiakova Lioudmila Tretiakova
Senior Research Gemologist, Ph.D., G.G.

Expertise: Diamonds, Colored stones, Minerals.

Lioudmila Tretiakova is a graduate of St. Petersburg State Mining Institute (Russia) with a MS in geology and a Ph.D. in mineralogy and spectroscopy. She also has a G.G. Diploma in gemology from the Gemological Institute of America. For last 25 years, she has been a professional research scientist of mineralogy and gemology. Lioudmila has authored many articles and patents, and has presented her research on "Nondestructive gem identification technique" at many International Gemological Symposiums. She had the opportunity to examine and analyze the mineralogical and gemological collections from St. Petersburg Mining Museum and jewelry collections from famous St. Petersburg Art Museums (Russia). Scientific interests: gems, minerals, their origin, treatment, enhancement, spectroscopic methods of nondestructive gem identification.
Jennifer Vichinsky Jennifer Vichinsky
Senior Gemologist, Gem Certification and Assurance Lab (GCAL)

Expertise: Diamonds.
Other Areas: Colored Stones.

Jennifer Vichinsky holds a Bachelor of Science degree in Facility Management (architectural design and layout) from SUNY @ Buffalo. Her design interests lead her to the Gemological Institute of America (GIA) where she studied Jewelry Design, Gemology and Jewelry Manufacturing. After graduating from GIA with a Graduate Jeweler Gemology Diploma, Jennifer spent several years in retail jewelry sales and appraising. She subsequently acquired a position teaching Gemology (Diamonds and Colored Stones) at the GIA in New York City. Since 1999, Jennifer has worked with Don Palmieri in a laboratory setting, honing her skills as a diamond and colored stone grader and appraiser. Her proficiency in evaluating all facets of diamonds and their structure lead to her position as Senior Gemologist at GCAL.
Sharrie Woodring Sharrie Woodring
Senior Gemologist, Gem Certification and Assurance Lab (GCAL)

Expertise: Diamonds and Colored Gemstones.

Sharrie Woodring is a lifelong collector of gems and minerals and began lapidary work (cutting gemstones) at age 12. She holds a Graduate Gemologist diploma from the Gemological Institute of America and a diploma from the Gemological Association of Great Britain, earning the right to use the initials F.G.A. (Fellow of the Gemological Association.) She has written numerous articles and co-authored a book about synthetic diamonds. She also lectures at trade events around the world and has appeared on television as a gem industry expert.