Jewelry designer Sandra Gronstra sorts sea glass outside her Swampscott studio.
By STACEY MARCUS
It seems like Sonja Grondstra was destined to be connected to the sea. The Swampscott jewelry designer collects pieces of sea glass from the nearby shores to create stunning handcrafted necklaces, bracelets, rings, pendants, earrings and pins that are featured in more than 60 boutiques throughout the country. Locally, you can find her work at Kats Boutique on Humphrey Street—just a few steps from where she finds her treasures, before transforming them in her Ingalls Terrace studio.
Jewelry making is woven into Grondstra’s DNA. Her late Oma (grandmother), who was born in Holland, was a silversmith and jewelry designer. Grondstra’s mother, Ine, a graduate of the Museum School of Fine Arts, resides in Oaxaca—a burgeoning cultural and culinary capital of Mexico—where she creates art and jewelry. Grondstra is a graduate of Salem State University, where she earned her degree in geography, with a concentration in travel and tourism. Her early career was focused on travel and retail, but an assignment through her metalsmith class at the Massachusetts College of Art led her to her true passion. 
“I had to choose an object that reflected the environment,” says Grondstra, who incorporated various shades of green beach glass into the shape of a palm tree. The project was the spark of an idea that would light up her life.
She followed up her metalsmith class with additional training in goldsmithing and jewelry design and got hooked on creating bezel-set jewelry featuring sea glass.
“My family was far away and I found home by walking on the beach with my black lab, Randy,” she says. “Twenty years ago I could sit on the beach and find beautiful beach glass, but there’s not as much today due to recycling and more people picking it up.”
She still loves to comb beaches in the islands of Maine and on the shores of Swampscott, Marblehead and Gloucester.
When her Oma passed away, Grondstra decided to dedicate her jewelry to her and created an “Ocean Angel” talisman from a treasured piece of sea glass. Her signature series is now called “Oceans Apart.”
“I was so thrilled that someone would pay money for one of my pieces,” she says of the original collection. Her work has been featured at trunk shows and exhibitions at Marblehead Arts Association, Bloomingdale’s, Peabody Essex Museum, Museum of Fine Arts and Saks Fifth Avenue. She has also participated in more than 90 juried retail shows and possesses over 15 years of wholesale show experience. 
Throughout the years, Grondstra has created hundreds of unique pieces. She began adding pearls, semi-precious stones, beach pottery and recycled glass to create a refined line.
Her family shares her affinity for the sea. Her husband, Mike Purcell, enjoys fishing and water sports and has been a Merchant Marine for more than 25 years. He sails on a ship called the APL Agate as a chief engineer, shipping out to Southeast Asia and beyond. Their son, Lars, is an avid sailor. He set up a booth with the Friends of Swampscott Sailing earlier this year to offer sailing program activities at Fisherman’s Beach as part of his Eagle Scout project.
Photos: Paula Muller
