Add-on Diamond in the rough, opal, Herkimer charm gold filled

Untamed mineral light and shifting prismatic colour to personalise your everyday pieces 24/7.

Looking for an effortless way to bring natural dimension and subtle luminescence to your daily jewellery without buying an entirely new piece? The add-on Diamond in the Rough & opal charm captures the unpolished beauty of raw earth in an elevated, geometric diamond-shaped silhouette. Fitted with a smooth, seamless connecting bail, this natural rough opal drop slides fluidly onto our click-close huggie oorbellen or threads onto a delicate necklace chain. As the light hits its raw, natural contours, the genuine opal reveals quiet flashes of fiery coral, luminous green, and pastel blue, adding organic texture to a minimal gold hoop or serving as an ethereal focal point in an ear stack.

Most add-on gemstone charms present familiar daily frustrations: paper-thin flash plating that wears down to dull base metal after a single holiday, flimsy wire wraps that catch on knitwear, or weak jump rings that pull open and drop your stone down the sink. We craft our pieces for real daily living. Handcrafted using authentic 14k gold filled hardware (also available in .925 sterling silver), the thick layer of solid 14k gold is mechanically heat- and pressure-bonded to the core. It is 100% waterproof, sweat-resistant, and hypoallergenic. The sturdy, fine bail is engineered for dependable durability while maintaining a clean, delicate profile. You can lather up in the shower, head out for a swim, power through a workout, and sleep undisturbed on your side without worrying about peeling coatings, green skin, or losing your favourite charm.

Because we source genuine, unrefined natural opals, each stone carries its own organic crystalline matrix, milky undertones, and iridescent play of colour, making your charm completely one of a kind.

step 1. Choose your favourite charm or gemstone.

step 2. Choose what kind of jewellery the add-on is for. For necklaces/bracelets we will add a large jump ring so you can slide the add-on onto necklaces yourself.

for earrings The rings on top of the charms are 3mm in diameter and are a perfect fit for our basic hoop earrings. If your own earring has a different thickness, please let us know in a message so we can adjust the fit of the charm.

for a necklace/bracelet For a necklace/bracelet we will add an extra jump ring so you can slide the charm onto your piece yourself. If you'd like us to attach the charm to a piece of jewellery in your order, please let us know in a message with your order.

Charm is 14k gold filled
Genuine gemstones
Sold per piece
Handmade in Amsterdam

opal
Opal is a hydrophane stone, especially white opal, which means that it can change colour when it comes into contact with water. It's important to remove your opal jewellery before taking a swim, shower, or workout.

high quality materials
We exclusively use .925 sterling silver, 14k gold filled & 5 micron vermeil gold so you can enjoy your pieces every day without them losing their colour.

custom & comfortable fit
Elevate your favourite chains & earrings with one of our add-ons - the perfect way to tell your story! Lightweight and designed for all-day wear.

versatile
From genuine birthstones, to personalised pendants, there are infinite ways to turn your memories into keepsakes.

sustainable
Sterling silver, gold filled, and vermeil can be recycled to be made into something new; nothing goes to waste.

handmade quality
Each piece is handmade by Roxy in our Amsterdam atelier, or designed in Amsterdam and handmade in Thailand.

We exclusively use 14k gold filled, .925 sterling silver, and 5 micron vermeil gold. Perfect for everyday wear! All the gemstones & freshwater pearls we use are genuine. You can find detailed descriptions of all the materials we use and how to care for them here.

All pieces are handmade with a lot of love. With that and sustainability in mind, not all sizes or pieces of jewellery can be returned or exchanged. Check the Info tab if this piece has a standard size. Earrings can only be returned if they're unworn. You can read our full return policy here.

Do you have an idea in mind for a special piece of jewellery? The beauty of handmade is the endless possibilities to make your idea come to life!

Know what you want? Leave your request in the text box in your cart when placing your order.

Need some advice? Use our live chat or send us an e-mail (info@koiatelier.com) and Roxy will get back to you ASAP.

Want to pick your own gems and get some personal advice? Book a personal shopping appointment with us at the atelier to experience Koi in full!

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Add-on Diamond in the rough, opal, Herkimer charm gold filled

Koi Atelier