Online Division
designed for working professionals


GIA instructors are passionate educators who bring years of industry experience to the classroom. All are leaders in their fields, and all are dedicated to helping you gain knowledge, acquire skills and launch your career.


Mariam Aboushadi

Mariam Aboushadi

Fascination with diamonds and gemology starts at the microscopic level for Mariam. She views the intricacies of every stone as gateways into its development and journey. With a B.S. in Biology, she approaches each stone with a meticulous application of the scientific method.

Heather Weishaar Cason

Heather Cason

Heather’s interest in jewelry stems from her love of art and design. This led her to her first job as a jeweler’s apprentice. After attending the University of Arizona, her interest in gems and jewelry grew, and she earned the Graduate Gemologist and Graduate Jeweler diplomas. Heather initially came to GIA with the intention of learning jewelry manufacturing and design, but ended up falling in love with gemology. With a newfound interest in gemology, Heather took a position as a wholesale gem sales representative and then managed a retail jewelry store. As Supervisor for Online Education, Heather shares her years of experience and love of gemology.

Lo Comb

Lo Combs

Surrounded by gems and antique jewelry from a young age, Lo has always been fascinated with the industry. From polishing silver at her father’s antique business to watching the local bench jeweler at the jewelry store where her mother worked, Lo spent considerable time learning and observing the trade from the inside. After earning a B.A. in Creative Process and Aesthetics of Music Performance and Studio Art from the University of Redlands, Lo furthered her education at GIA by earning the Graduate Gemologist and Accredited Jewelry Professional diplomas. Her work as a jewelry consultant, as a diamond grader in the GIA Laboratory, and regular attendance of gemological tradeshows demonstrates her commitment to the trade and desire to further enrich her knowledge and experience. Lo’s passion for gemology fuels and inspires her role as an instructor, where she strives to give her students the best opportunity for success in their gemological endeavors.

Headshot of distance education faculty member Bethany Crane

Bethany “Bess” Crane

Bethany’s love of jewelry began when she was very young, going through the jewelry collection her grandmother gathered on her world travels. Her father instilled in Bethany a love of art and antiques, and these interests often intersected. She earned a Bachelor of Science in Print Journalism from Utah State University. After learning of GIA and working in other industries for a time, Bethany knew that GIA was where she wanted to be to pursue her passion for gems and jewelry. After earning her GIA Graduate Gemologist and Applied Jewelry Professional diplomas, she worked in quality control and client services for several retailers. Bethany enjoys sharing her enthusiasm for gemology with students and friends alike.

Don Hofler

Donald Hofler

Donald Hofler brings his curiosity and thirst for knowledge from a young age into the gem and jewelry industry. With a GIA Graduate Gemologist diploma and credentials in accounting, organizational leadership, and jewelry, he has a passion to research, acquire, and test a multitude of fine gems. He has worked in sales management, accounting, and aerospace inspection, combining precision requirements and drive with his love for gems and jewelry. Don specializes in minerals and colored stones, always looking for new and novel pieces. In fact, he considers one of his greatest accomplishments to be the introduction of a new purple pink color of diaspore to the GIA laboratory. The article was featured in the Summer 2020 Gems & Gemology issue.

Noah Leverton

Noah Leverton

Noah Leverton has journeyed from working in watch and jewelry sales at Fraser Hart in Edinburgh, Scotland to diamond grading at GIA in Carlsbad to teaching online gemology courses at GIA. During his seven years in GIA’s laboratory, he helped train new diamond graders and staff. He then earned the GIA Graduate Gemologist diploma through online education before joining GIA Education’s Online Division as an instructor. He loves explaining complex concepts in a way that sparks students’ interest, and his goal is to prepare students so that they’re confident and knowledgeable enough to succeed in their dream gemology careers. In his free time, Noah enjoys playing basketball and used to train new referees.

Paul Mattlin 120x120

Paul Mattlin

As Senior Manager of Online Education instruction at GIA, Paul brings a lifelong passion for gemstones and minerals along with more than 10 years of trade experience. Paul completed both the Graduate Gemologist and Graduate Jeweler diplomas, which he utilized extensively while working in retail jewelry sales and management selling luxury watches and owning a small boutique jewelry business that specialized in unique gemstones. With a background in web design and systems engineering, Paul is savvy about using technology to help students learn.

Michele Mejia Faculty headshot

Michele Mejia

Michele’s fascination with jewelry began while working for a local pawn shop. Over the next 23 years, she helped build the small shop into a corporation with multiple locations and business functions. Throughout this time, she also managed and trained the sales staff. Intent on learning more about gemstones, she pursued her Accredited Jewelry Professional (AJP), Graduate Pearls and Graduate Gemologist diplomas through GIA as an Online Education student. After graduating from GIA, Michele assisted other pawn shops with training staff, identifying gemstones and grading diamonds. When an instructor position became available at GIA Carlsbad, she knew instantly that helping students learn about gems would be a rewarding experience and the perfect fit for her interests.

Daniela Pacheco 120x120

Daniela Pacheco

Daniela’s interest in natural geological formations started in her youth. She followed it by earning the Graduate Gemologist diploma and Accredited Jewelry Professional credential while working as a GIA diamond grader from 2014-2017. Daniela also loves the visual arts, and completed her Bachelor of Fine Arts at BIOLA University in 2014. Her favorite part of being an instructor is witnessing the “aha!” moment when students understand the gem identification process.

Trang Pham

Trang Pham

Trang Pham has experience as both a store owner and a professional jewelry appraiser and has collaborated with the Department of Justice to provide appraisals for forfeited property processing. In 2016, her vision was to establish a business that could create job opportunities for local women in Vietnam. Fueled by her childhood hobby, Trang crafted hand-wire-wrapped, cabochon jewelry and eventually expanded into diamond jewelry. After relocating to San Diego, earning the Graduate Gemologist diploma from GIA marked a pivotal moment in her career, opening the door to her second profession as a jewelry appraiser. Trang is enthusiastic about sharing the knowledge she has acquired. Her practical insights from her journey in the trade lend a unique dimension to her instruction, inspiring students to pursue their passion for gemology.

Glenn Wargo Faculty 120x120

Glenn Wargo

Glenn’s passion for gems and jewelry started in grammar school when a family friend gave him a collection of rocks from around the world. He pursued his love of things gemological in his youth by working as a bench jeweler apprentice and earning a Bachelor of Arts in jewelry design from Montclair State University. Glenn went on to work in sales for Fortunoff and Tiffany & Co, and received his GG from GIA in 1995. On teaching at GIA: “It allows me to give back to students what I’ve learned about designing, selling and studying. I enjoy teaching and watching students grow and develop their skills.”

Danielle Yamamoto

Danielle Yamamoto

Dani’s interest in gemology began during her childhood in the Mojave Desert, where she searched for rose quartz, obsidian arrowheads and geodes. She went on to earn a B.A. in English and taught high school English for the Los Angeles Unified School District. Danielle later pursued her childhood passion, earning the Graduate Gemologist diploma. Before becoming an Online Education instructor at GIA, Dani worked in e-commerce diamond sales and at a brick-and-mortal jewelry retail store. She was also a diamond, colored stone and Swiss watch buyer. Gem Identification is her favorite part of the Graduate Gemologist program, because identifying a gemstone is like solving a small mystery. Dani says, “It’s fun and satisfying, and it’s a skill that makes a person valuable in the jewelry buying world.”