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Helena 0.50 ct Moissanite Engagement Ring in 18K Gold

Q: How do I find my ring size? And what if I get it wrong?

We offer the first ring size adjustment free of charge within 12 months of receiving your order. To ensure a more accurate measurement, we recommend having your finger sized at a jewelry store with a ring sizer. Additionally, we send a complimentary ring sizer with your order to facilitate this process. If you prefer, you can also consult our Size Guide .

Q: What's the difference between natural diamond, lab-grown diamond, and moissanite?

Natural Diamond : formed by nature over billions of years, extracted from mines. Each stone is unique, carrying rarity and history. Lab-Grown Diamond : produced with advanced technology, but with the same composition and properties as a natural diamond. Visually and chemically identical to natural diamonds, differing only in origin. Moissanite : a gemstone created in a laboratory from silicon carbide. It is not a diamond, but it has a very intense brilliance and even more colorful "fire," high hardness (9.25 on the Mohs scale), and a more accessible cost, making it a modern and durable alternative for engagement rings.

R$ 2.490,00

Size:

Size Guide

Measure an existing ring

To find your size, measure the internal diameter (in millimeters) of a ring that already fits you well. Place the ring on a ruler/caliper and measure the inside from edge to edge. Compare with the table:

BR Size	Internal Diameter (mm)
10	15.0
11	15.1
12	15.2
13	16.0
14	16.1
15	17.0
16	17.1
17	17.2
18	17.5
19	18.0
20	18.5
21	18.8
22	19.0
23	19.2
24	19.9
25	20.0
26	20.5
27	20.8
28	21.1
29	21.2
30	21.8
31	22.1
32	22.5
33	22.8

Tip: Measure at the end of the day and avoid measuring with cold fingers. If you're between two sizes, the larger one is usually more comfortable. If in doubt, contact us.

Can't find the size you're looking for? Click here to get in touch with our team for assistance!

Measure your finger (paper strip or string)

If you don't have a ring as a reference, use a paper strip (or string) to measure the circumference of your finger and convert it to your ring size.

Cut a thin strip of paper (±5 mm wide) or use a thin string.
Wrap it around the finger where the ring will be worn. (Don't overtighten; simulate real comfort.)
Mark the meeting point with a pen.
Lay the strip flat and measure the distance between the marks in centimeters (cm).
Use your measurement in centimeters to find the corresponding size in the table below.

Reference table – finger circumference (cm) × BR size:

BR Size	Finger Circumference (cm)
10	4.8
11	4.9
12	5.0
13	5.1
14	5.2
15	5.3
16	5.4
17	5.5
18	5.6
19	5.7
20	5.8
21	5.9
22	6.0
23	6.1
24	6.2
25	6.3
26	6.4
27	6.5
28	6.6
29	6.7
30	6.8
31	6.9
32	7.0
33	7.1

Important: Ensure the measurement passes over the knuckles (the widest part of your finger). If you are between two sizes, please contact us to confirm — the 1st adjustment is free.

Colour:Yellow Gold

Variant

Gem Type:

Moissanite

Complimentary Engraving

Personalize your dream ring with an engraving. If you wish to add this to your ring, it will be laser engraved on the inside of the band.*Up to 15 characters.

A name, a date, initials or a word...

Prazo de Produção 4 dias úteis

Envio Calcule pelo CEP

Calcule a previsão para seu endereço

Previsão estimada de entrega

Como calculamos o prazo?

A previsão considera o tempo de produção da joia, a preparação do pedido e o prazo estimado de transporte para o CEP informado.

O prazo de produção começa após a confirmação do pagamento. Sábados, domingos e feriados não são considerados dias úteis.

O envio é realizado via SEDEX com seguro. A previsão pode sofrer alterações em feriados, restrições operacionais dos Correios ou eventos fora do controle da Vangolden.

1st Free Adjustment

18K Solid Gold

Insured Shipping

The Helena Ring is an 18K gold solitaire that relies on the strength of simple lines.

The smooth and delicately rounded band guides the eye to the 0.50ct emerald-cut moissanite, with straight facets. Set in four prongs, the stone is well exposed, with front and side light entry.

It is a clean, elegant, and contemporary piece of jewelry.

Technical details

Metal Type: 18K Gold
Center Stone Shape: Emerald 5.0mm x 3.0mm (approximately)
Average Band Width: 1.70mm
Average Thickness: 1.50mm

Moissanite
GRA Certificate Available
Total Accent Stone CT: 0.50 CT
Average Accent Stone Color: D
Average Accent Stone Clarity: VVS1

Warranty & Adjustments

Lifetime warranty for the 18K gold content and all gems used.
All orders come with our certificate of authenticity and warranty, gem certificate (when applicable), and invoice.
90-day warranty against any manufacturing defects.
First ring size adjustment free of charge, if needed within 12 months of receipt.

For more details on warranty, adjustments, and care, please see our Frequently Asked Questions (FAQ).

Shipping & Delivery

This piece is available for immediate deliveryand will be shipped within 4 business daysafter payment confirmation.

Shipping is done via SEDEX. Shipping is free for the South and Southeast regions, and for other regions, it is calculated at checkout according to the zip code.

After shipping, you will receive a tracking code to monitor the delivery.

Care

Remove jewelry before using perfumes, creams, makeup, sunscreen, and cleaning products, as they can damage metals and stones.

Store each piece of jewelry separately, in velvet pouches or boxes with dividers, to prevent scratches and damage.

Clean with warm water, mild soap, and a soft-bristled brush. Rinse thoroughly and dry with a soft cloth.

Read more about it in our Care Guide.

Helena 0.50 ct Moissanite Engagement Ring in 18K Gold

R$ 2.490,00

Types of Gemstones

We work with three options for the center stone: Moissanite, Lab-Grown Diamond, and Natural Diamond. All are durable for daily wear. The ideal choice depends on desired brilliance, origin, and budget.

Moissanite

Intense brilliance and "fire" (greater dispersion than diamond).
High durability: hardness ~9.25 on the Mohs scale.
Excellent cost-benefit: striking appearance at an accessible price.
Available in various sizes and cuts.

Lab-Grown Diamond

It's a real diamond! (same physical and chemical composition)
Visually identical to natural, with a better size/price ratio.
Produced in a controlled environment; Gemological certificate for gems over 1 ct (upon request).

Natural Diamond

Rarity and tradition: formed in nature over millions of years.
Maximum hardness (10 Mohs) and classic diamond brilliance.
Available with gemological certification for gems over 0.30ct (upon request)

Quick Comparison

Characteristic	Moissanite	Lab Diamond	Natural Diamond
Composition	Silicon carbide (SiC)	Crystalline carbon (C)	Crystalline carbon (C)
Hardness (Mohs)	~9.25	10	10
Brilliance / Fire	More "fire" (greater dispersion)	Classic diamond brilliance	Classic diamond brilliance
Origin	Laboratory	Laboratory	Natural
Relative Price	$$ (more accessible)	$$$	$$$$
Certification	GRA above 0.50ct	Certificate upon request above 1 ct	Certificate upon request above 0.30ct

Note: The final appearance depends on factors such as cut, color, and clarity of each piece.

How to choose?

Visual impact and best price → Moissanite.
Diamond with great cost/size ratio → Lab-Grown Diamond.
Rarity and traditional value → Natural Diamond.

Still in doubt? Talk to our team — we'll help you compare sizes, colors, and cuts within your budget.

Durability

Moissanite occupies a unique position: it does not replace diamond, but it is the closest alternative in terms of brilliance, strength, and durability.

Luminosity

Moissanite stands out for its intense brilliance and vivid play of colors, a result of a higher refractive index than that of diamond.

Authenticity and Classification

All moissanites above 0.50ct come with a GRA certificate, which ensures the authenticity, specifications, and quality of the gem.

Need help?

FAQ — Frequently Asked Questions

To access the complete page on all Frequently Asked Questions (FAQ) click here.

You can also visit our Exchange, Return, and Refund Policy page to clarify the most common questions about customizations, adjustments, and exchanges.

How do I find my ring size? And what if I get it wrong?

We offer the first ring size adjustment free of charge within 12 months of receiving your order.

To ensure a more accurate measurement, we recommend having your finger sized at a jewelry store with a ring sizer.

Additionally, we send a complimentary ring sizer with your order to facilitate this process. If you prefer, you can also consult our Size Guide.

What guarantee do I have?

Vangolden offers a lifetime guarantee on the authenticity of the raw materials used in its jewelry, including 18K gold (750 purity), natural and lab-grown diamonds, natural colored gemstones, and Moissanites.

All orders come with our certificate of authenticity and guarantee, a gemstone certificate (when applicable), and an invoice.

In addition, all jewelry has a legal warranty of 90 (ninety) calendar days, counted from the date of receipt, in accordance with the Consumer Protection Code, to cover any manufacturing defects.

The warranty does not cover:

Damage caused by drops, impacts, or misuse;
Breakage or loss of stones due to improper handling;
Scratches or natural wear and tear due to continuous use;
Oxidation or color change caused by contact with chemical products (e.g., perfumes, creams, swimming pool);
Damage due to incorrect storage or lack of periodic maintenance;
Pieces modified, adjusted, or repaired by unauthorized third parties.

You can find more information about warranty, adjustments, and care in the Frequently Asked Questions (FAQ).

How is my order shipped?

You will receive an email and WhatsApp message with the tracking code once it has been shipped.

Shipping is done via SEDEX with insurance against theft and loss. Shipping is free for the South and Southeast regions, and for other regions, it is calculated at checkout according to the zip code.

Average delivery times vary by location:

Capital cities: 1 to 4 business days
Rural areas: 2 to 7 business days

You can find more information about shipping and delivery times in our Shipping Policy.

Gems and Raw Materials

Is moissanite a diamond?

No. Although visually similar, moissanite and diamond are different minerals. Moissanite is made of silicon carbide, while diamond is crystallized pure carbon.

What's the difference between natural diamond, lab-grown diamond, and moissanite?

Natural Diamond: formed by nature over billions of years, extracted from mines. Each stone is unique, carrying rarity and history.

Lab-Grown Diamond: produced with advanced technology, but with the same composition and properties as a natural diamond. Visually and chemically identical to natural diamonds, differing only in origin.

Moissanite: a gemstone created in a laboratory from silicon carbide. It is not a diamond, but it has a very intense brilliance and even more colorful "fire," high hardness (9.25 on the Mohs scale), and a more accessible cost, making it a modern and durable alternative for engagement rings.

Does Moissanite lose its sparkle over time?

No. Like diamonds, it maintains its brilliance and transparency throughout its life, provided it receives basic cleaning and care.

What does "18k" mean in jewelry?

“18k” indicates that 75% of the alloy is pure gold and 25% consists of metals that provide strength and color. It is the most commonly used standard in fine jewelry due to its combination of beauty and durability.

BR Size	Finger Circumference (cm)
10	4.8
11	4.9
12	5.0
13	5.1
14	5.2
15	5.3
16	5.4
17	5.5
18	5.6
19	5.7
20	5.8
21	5.9
22	6.0
23	6.1
24	6.2
25	6.3
26	6.4
27	6.5
28	6.6
29	6.7
30	6.8
31	6.9
32	7.0
33	7.1

BR Size	Finger Circumference (cm)
10	4.8
11	4.9
12	5.0
13	5.1
14	5.2
15	5.3
16	5.4
17	5.5
18	5.6
19	5.7
20	5.8
21	5.9
22	6.0
23	6.1
24	6.2
25	6.3
26	6.4
27	6.5
28	6.6
29	6.7
30	6.8
31	6.9
32	7.0
33	7.1

Installment	Total
1x R$ 2.490,00 with no interest	R$ 2.490,00
2x R$ 1.245,00 with no interest	R$ 2.490,00
3x R$ 830,00 with no interest	R$ 2.490,00
4x R$ 622,50 with no interest	R$ 2.490,00
5x R$ 498,00 with no interest	R$ 2.490,00
6x R$ 415,00 with no interest	R$ 2.490,00
7x R$ 355,71 with no interest	R$ 2.490,00
8x R$ 311,25 with no interest	R$ 2.490,00
9x R$ 276,67 with no interest	R$ 2.490,00
10x R$ 249,00 with no interest	R$ 2.490,00
11x R$ 226,36 with no interest	R$ 2.490,00
12x R$ 207,50 with no interest	R$ 2.490,00

BR Size	Finger Circumference (cm)
10	4.8
11	4.9
12	5.0
13	5.1
14	5.2
15	5.3
16	5.4
17	5.5
18	5.6
19	5.7
20	5.8
21	5.9
22	6.0
23	6.1
24	6.2
25	6.3
26	6.4
27	6.5
28	6.6
29	6.7
30	6.8
31	6.9
32	7.0
33	7.1

BR Size	Finger Circumference (cm)
10	4.8
11	4.9
12	5.0
13	5.1
14	5.2
15	5.3
16	5.4
17	5.5
18	5.6
19	5.7
20	5.8
21	5.9
22	6.0
23	6.1
24	6.2
25	6.3
26	6.4
27	6.5
28	6.6
29	6.7
30	6.8
31	6.9
32	7.0
33	7.1

Helena 0.50 ct Moissanite Engagement Ring in 18K Gold

Measure an existing ring

Measure your finger (paper strip or string)

Complimentary Engraving