Somewhere Over the Rainbow

Happy Birthday September!

SK alas blue

Your traditional, and stunning, birthstone is sapphire. There’s no way around the ample beauty of this gorgeous gemstone.

purple MBE

Stick to tradition and look for the blue hued beauties – the shades of cool complexity. This is your time to celebrate you, so dive into the deep blue and make all your birthday dreams come true!

MG enclosed pendant

Though, sapphires are not only blue, they come in almost every color of the rainbow: red, pink, yellow, orange, green, peach, and violet colors. The most sought-after color fancy Sapphire is the rare and beautiful Padparadscha: a pink-orange corundum with a distinctive salmon color reminiscent of a tropical sunset. So step outside the box and choose a sapphire that is somewhere over the rainbow!

JB pendant

Each sapphire is totally and completely unique, though all measure a 9 on the Moh’s hardness scale (listed on this scale as corundum).  Diamond comes in as the hardest material on Earth at a 10.

MBE white

When picking your special colored sapphire, choose a color that is special to you, something that makes you feel good. It is your birthday, after all!

MBE studs

Here are some more sapphire heirloom treasures that will be cherished for generations to come…

JJ linen  gurhan venus gkcanoes gk trillium GK lilac BH pink ring BH natural blue BH marquis earrings BH flour flat asp wrap as flora dome af earring AF RRO ringimage029

Shop our entire collection of sapphire jewelry, and get celebrating!

Petals to the Metal!

Never underestimate the power of flowers – especially when they are eternally stunning!


petals John Iversen, Paul Morelli, Gabriella Kiss, Barbara Heinrich, Julez Bryant, Sethi Couture and more… these artists show us the true meaning of natural beauty.

Feminine, delicate and each unique – create your own bouquet!

Happy 4th of July from Quadrum!


Best of Boston 2017!!! Best Fine Jewelry!

We are thrilled to announce that we have won Boston Magazine’s Best of Boston ® 2017 Best Jewelry, Fine in Boston! It is such an incredible honor to be receiving this highly esteemed recognition for two consecutive years.

It all started with the great vision that Quadrum’s owner, Cynthia Kagan, had 39 years ago; to open a gallery that would give space for contemporary jewelry artists to showcase their work. She worked tirelessly to make Quadrum what it is today, and we are now blessed with an amazing staff who continue the tradition of putting their all into curating and representing the finest artist jewelry collection around. Director Sia Maravelias, Assistant Director Amy Renneisen, and the Quadrum staff are intensely focused on this field of artistic expression, as shown in their passion, energy, and devotion. It is by providing an extensive level of customer service that your experience will be unsurpassed and met with the ultimate satisfaction that comes with giving or wearing a beautiful piece of jewelry.


Quadrum is truly a place of discovery and inspiration. As we are always on the hunt to bring new, extraordinary artists to the gallery, Quadrum has become known as a destination for new discoveries. It is also notable that Gabriella Kiss, John Iversen and Pat Flynn and Reinstein/Ross have been working with us for over 25 years. One of our artists stands out for having been with Quadrum for over 32 years – Barbara Heinrich!


If you are looking for a relaxed and ultra-luxe shopping experience, Quadrum’s beautiful museum-like setting and dramatically lit jewel-boxes immediately offer a new appreciation for artist-made jewelry. You will see the beauty and intricacy of each piece and come to experience the involvement of the most exquisite materials. Our vast collections from a a carefully curated range of exclusive artists from around the world will unite you with an answer for every aesthetic and taste.


Our artists include: Alex Sepkus, Amali, Anne Sportun, Annette Ferdinandsen, Annie Fensterstock, Anthony Lent, Barbara Heinrich, Edward Burrowes, Gabriella Kiss, Gellner, George Sawyer, Gurhan, Henrich & Denzel, Jamie Joseph, John Iversen, Joseph Brooks, Julez Bryant, Lilly Fitzgerald, Maria Beaulieu, Mortiz Glick, Nathan Levy, Pat Flynn, Paul Morelli, Polly Wales, Reinstein/Ross, Rosanne Pugliese, Sethi Couture, Sorellina, Spinelli Kilcollin, Todd Pownell, Todd Reed, and Yossi Harari.


Among these reputable and innovative artists’ collections will find the most exquisite choices of one-of-a-kind uniquely cut gemstones, sparkling diamonds, South Sea and Tahitian pearls, 18K, 20K, 22K and pure 24K gold, platinum, sterling silver, bronze and stainless steel all of individual artistic expression. These pieces embody a sense of both style and rarity; they are works of art that intensify life’s most celebratory and memorable moments; beautiful jewelry that stands the test of time.


Please accept our warm invitation to explore the ultimate in elegance, and discover our distinctive collection of artist jewelry coupled with impeccable service.