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EspañolDesign your own piece to your exact wishes in our configurator
Choose the metal, size, diamond and engraving – we'll take care of the rest.
IGI / GIA
in the Czech Republic
with GLS across Europe
free
About the piece
The Formosa engagement ring puts a marquise-cut centre stone in the spotlight. Marquise side diamonds follow on either side, while the twisted band is lined with a pavé of small round diamonds.
The centre diamond – lab-grown or natural – is selected directly with the piece; the price shown is without the stone. On request, we can adjust the piece to your specification – for example the diamond size, cut or other details. Engraving is free of charge; you provide the text directly with your order.
- Side diamonds
- 4 pcs markýza 4×2 mm + 18 pcs 1.30 mm, E-F / VVS-VS
- Approximate weight
- 3.52 g
We will tailor the piece to your wishes. On request, we can set any other diamond shape or size into it and adjust the design to your specifications – just drop us a message.
Warranty: we provide a warranty on jewellery and diamonds in accordance with the terms and conditions of ULTIMATE-GEMS s. r. o.
free
or exchange
with every diamond
of your piece
What our customers say
“I think I've bought from almost every company on the Czech market, and I have to honestly admit that I truly regret some of those experiences — though that certainly doesn't apply to Mr Auředník, who is incredibly down-to-earth.”
Šárka M.“When I started looking for a lab-grown diamond supplier, I approached 3–4 companies. It was here that won the selection process — through their approach and quick response.”
Martina Vernerová“I appreciate the owner's welcoming approach. The pendant is beautiful. When I have my next big anniversary, I'll happily buy another piece.”
Michal OuškaFrequently asked questions
How do I find out my correct ring size?
Measure the inside diameter of a ring that fits you well, or the circumference of your finger with a piece of thread — then compare it with our size chart (the “How to determine the size?” link next to the size selection). If you're not sure, message us on WhatsApp and we'll be happy to help. The size can also be adjusted free of charge after delivery.
How long does it take to make a piece of jewellery?
Every piece is made to order, exactly to your configuration. Production takes approximately 2–4 weeks. Before dispatch, we will send you photos of the finished piece.
Will I receive a certificate with the diamond?
Yes, we supply an international IGI or GIA certificate with every diamond, confirming its parameters (carat, colour, clarity and cut).
Can I return or exchange the piece?
Yes, you have 30 days to return or exchange it, plus lifetime free servicing of the piece.
What warranty do you offer?
We provide a warranty on jewellery and diamonds in accordance with the terms and conditions of ULTIMATE-GEMS s. r. o. We also supply an IGI or GIA certificate with every certified diamond.
Can I have a different diamond shape or size set into the piece?
Yes. On request, we can set any other diamond shape or size into the piece and tailor it to your wishes. Message us on WhatsApp or by email and we will prepare a quote.
How much does delivery cost?
Delivery across Europe by GLS costs 30 EUR (free within the Czech Republic and Slovakia). The parcel is always insured and your piece arrives in elegant gift packaging.
How to determine your ring size
Measure the inside diameter of a ring that fits you, or the circumference of your finger with a piece of thread, and compare it with the chart. We're also happy to help via WhatsApp.
| US | EU circumference (mm) | Diameter (mm) |
|---|---|---|
| 4 | 47 | 14,9 |
| 5 | 49 | 15,7 |
| 6 | 52 | 16,5 |
| 7 | 55 | 17,3 |
| 8 | 57 | 18,1 |
| 9 | 59 | 19,0 |
| 10 | 62 | 19,8 |
How Formosa Engagement Ring is made
Formosa Engagement Ring is not a stock item - it starts being made only once you choose the metal, size and a specific diamond in the configurator. We cast it and finish it by hand in our workshop in the Czech Republic, so every piece passes through the hands of a goldsmith. Production usually takes 2 to 4 weeks.
Metal and its color
The choice is 14K Rose Gold, 14K White Gold, 14K Yellow Gold, 18K Rose Gold, 18K White Gold, 18K Yellow Gold a Platinum. We rhodium-plate white gold to give it a deep white shade; platinum 950 is more durable and develops a matte surface over time, which can be re-polished at any point. The metal color also affects how the stone looks - in white metal a diamond appears cooler and optically cleaner, in yellow and rose metal it looks warmer.
Center diamond
You choose the stone separately, so you control the balance between size and quality according to your budget. We supply lab-grown diamonds with an IGI certificate and natural diamonds with a GIA certificate - either way you know exactly what you are buying. If you are not sure which to choose, write to us and we will recommend the combination of parameters that looks best on the hand.
Frequently asked questions
How do I find out my ring size?
The easiest way is to measure a ring worn on the same finger. If you are buying the ring as a surprise, choose an estimated size - we can adjust the size after the proposal, without any problem for most models.
How long does production take?
Usually 2 to 4 weeks from order confirmation and stone selection. We confirm the exact date by email; if you need a specific date, we will try to speed up production.
Can I customize the model?
Yes. We can change the band width, the shape and size of the stone, or the number of side diamonds. Write to us what you would like different, and we will prepare a design and a price.
Is engraving included in the price?
Yes, engraving text on the inside of the ring and luxury packaging are both free of charge. Delivery within the Czech Republic and Slovakia is also free of charge.
