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.

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.

Michele Lisso Faculty headshot

Michele Lisso

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 a Distance 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.

Paul Mattlin 120x120

Paul Mattlin

As Manager of Distance 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.

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.

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.”

Heather Weishaar

Heather Weishaar

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 an instructor, Heather shares her years of experience and love of gemology.

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 a Distance 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.”