Kelly Costello, designer of Salt & Water Co., on the beach
our designer

Born and raised in Hawaiʻi.

Kelly’s life has always been shaped by the ocean. It has served as both compass and refuge, offering grounding, perspective, and a steady reminder to slow down and observe what truly matters.

Her designs reflect this relationship with nature: intentional, uncomplicated, and quietly expressive. Each piece draws inspiration from the natural rhythms of island life and is crafted with care, honoring both the materials and the meaning they carry.

our story

A return to home, to where it all began.

Inspired by the South Pacific islands and the waters that shaped us, Salt & Water Co. was founded in 2023 by designer Kelly Costello. The brand was born from a desire for jewelry that feels both sophisticated and accessible: pieces that balance refinement with a deep connection to nature.

Rooted in Hawaiʻi and guided by craftsmanship, femininity, and place, each collection reflects the quiet beauty of island life. Designed for women at every stage, Salt & Water Co. creates pieces meant to be worn, lived in, and carried forward— jewelry that feels personal, intentional, and timeless.

Two polaroids of Kelly's shell necklaces held up against palm trees
Kelly swimming in clear turquoise water
Kelly from behind wearing long pink shell necklaces down her back
A handful of Hawaiian shells in cupped hands
Kelly walking toward the ocean at sunset
Kelly reaching up to pick plumeria in a white dress
Kelly swimming just under the surface of the ocean
Kelly holding a handful of shells beside her dive fins on the sand
Kelly Costello in a sea cave on Oʻahu

Thoughtfully sourced, personally gathered.

I personally gather shells and sea glass while diving and beachcombing around Oʻahu, collecting only empty shells and taking care to leave the surrounding environment undisturbed. My Tahitian pearls are sourced directly from Tahiti, while freshwater pearls and semi-precious gemstones are ethically sourced from trusted suppliers.

Some of my finds are on Instagram, @saltandwater_co.

The shell guide

How I source

Chosen for their natural beauty and individual character, each material brings something distinct to a piece. Mahalo for caring where your jewelry comes from.

  • I only collect empty shells, leaving those with living creatures inside in their natural habitat. Any shells or beach treasures I don’t end up using are returned back to the ocean.

    Collecting with care also means understanding and respecting the places we explore. Be mindful of local restrictions, leave occupied shells undisturbed, and respect the delicate ecosystems that make these treasures possible.

    Explore my shell guide to learn more about the shells I’ve found while diving around Hawaiʻi.

  • All Tahitian pearls are sourced directly from Tahiti, while freshwater pearls, including pink and white keshi, and semi-precious gemstones are carefully selected from trusted suppliers. Each pearl and stone is naturally unique, with subtle variations in color, shape, and texture that give every piece its own character.

    Explore more in the Pearl Guide and Gemstone Guide.

  • All pieces are handcrafted in 14k gold-filled or sterling silver, chosen for their durability and suitability for everyday wear, from days in the ocean to everything in between. 14k gold-filled consists of a thick layer of genuine 14k gold mechanically bonded to a base metal, offering the beauty of solid gold with lasting quality when properly cared for.

  • Every piece is thoughtfully handcrafted in small batches on the North Shore of Oʻahu, with an emphasis on intentional production, responsible practices, and respect for local craftsmanship.

  • Each piece is packaged with care, using recyclable materials and keeping unnecessary packaging to a minimum.

Our values

Handmade & locally sourced

Kelly drills every shell and pearl and makes each piece by hand, in small batches on the North Shore of Oʻahu.

Sustainability & ethics

Materials are ethically sourced with deep respect for the ocean and land, prioritizing responsible practices over excess. Sustainability isn’t a fixed destination, but an ongoing responsibility, guided by reflection, integrity and a deep connection to Hawaiʻi.

Craftsmanship

Quality, longevity, and attention to detail guide every design.

Intentional living

Pieces designed to be worn daily and lived in slowly, encouraging presence, simplicity, and connection to what matters most.

Connection to nature

Inspired by the healing power and understated beauty of the natural world.

Femininity

Celebrating strength, softness, and elegance in all stages of womanhood.

Kind words

So patient and kind

Kelly, the owner of Salt & Water was so kind, she literally was so patient with me and answered all of my questions and was awesome enough to show me all her beautiful sunrise shells so I could choose the perfect shell for my ring. She also customized a very special seashell that my dad found in Italy and made it into a beautiful necklace that I wear everyday. It meant so much to me since my dad is no longer here. Absolutely amazing work! Thank you Salt & Water ❤️

Valarie V.

Elmwood Park, IL

A little piece of the ocean

I came with just one thing I knew for certain, I wanted a strawberry drupe shell, and absolutely no idea what else! There was a huge collection of shells with tons of pictures, making it so easy to visualize everything and fall in love with combinations I never would have thought of on my own. Such a talent for guiding me through the process without ever making me feel pressured, helping me discover what I actually want one beautiful option at a time. The communication was clear from start to finish, and the final bangle turned out absolutely stunning, like a little piece of the ocean I get to wear everyday. It's everything I imagined and honestly so much more. If you've been dreaming of a custom shell piece, do yourself a favor and reach out!

Katelyn M.

Honolulu, HI

The colors flow so well

The colors flow so well. Thank you for being awesome! You made the process so seamless! And your communication was so good! I can’t wait to see the final outcome!

Tyler M.

Honolulu, HI

A reminder of Hawaiʻi

The most beautiful reminder of my Hawaii trip [custom sunrise shell bezeled pendant] -- I would go back in a heartbeat if I could.

Linnea B.

Marathon, IA

Mini & me

In love with my mini & me matching set! I was worried my baby would rip it and she LOVED it!

Marley J.

Honolulu, HI

So well done

Just got the earrings and anklet! I freakin love them both! So cute and so well done. You're so cute for throwing in the free little gift with your first purchase. Seriously I’m in love xoxo

Sarah A.

Haleʻiwa, HI