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0.5 Carat Rings

These 1/2 carat lab-grown diamond rings come with the center already set, and the price includes it. Choose from ten shapes and a range of styles: solitaires with plain or pave bands, a hidden halo, a vintage-style halo, a three stone ring, and side-accent designs. Each is offered in platinum or 10K, 14K or 18K white, yellow or rose gold, a simple path to a half carat engagement ring.

1Choose a setting
Choose a Setting
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2Select a diamond
Select a Diamond
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3Complete the ring
Complete the Ring
Preview & make it yours
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40 rings
40 rings
Conflict-Free
Ethically sourced diamonds
Lifetime Warranty
Free cleaning & resizing
Free Shipping
30-day returns
IGI / GIA Certified
Independently graded

Buying guide

Size and shape at half a carat

A 0.5 carat round lab-grown diamond is about 5 mm across. Oval, pear and marquise centers stretch that weight into a longer outline and look a little bigger from above, while princess, asscher and cushion shapes look compact and square. Emerald and radiant cuts sit between the two. Picking the shape you like best matters more at this size than chasing extra weight.

Styles that add sparkle

A plain solitaire keeps the look clean. A pave band, a hidden halo or a halo adds small lab-grown diamonds around or below the center, which makes the top of the ring look fuller. The three stone design and the marquise or pear side-accent styles widen the ring across the finger. Those accents add to the ring's overall stone weight; the 0.5 carat figure always means the center stone.

Metal choices

Platinum is naturally white and heavy, and it costs more. Gold comes in 10K, 14K and 18K, in white, yellow or rose. Lower karats wear harder, and higher karats show deeper color. The metal you choose changes the price more than the style does.

Made to order

Each ring is made for you in 10–15 days. Shipping is free on orders over $500, returns are accepted within 30 days, and one resize is free within 60 days of delivery.

0.5 Carat Rings FAQs

How much is a 0.5 carat diamond ring worth?

At RJ, a 0.5 carat ring with its lab-grown diamond center set starts under $800, and most are between about $1,050 and $1,200 in the lowest-priced metal. Platinum and 18K gold cost more. Lab-grown diamonds cost far less than natural diamonds of the same size, and they have little resale value, so buy the ring to wear rather than as an investment. The gold or platinum keeps its metal value.

Is a 0.5 carat diamond too small?

No. A half carat center is a popular size that looks neat and well proportioned on most hands, especially on a slim band. If you want it to look larger, choose an elongated shape such as oval, pear or marquise, or add a halo or pave band. Those accents add sparkle around the 0.5 carat lab-grown diamond center without changing its weight.

What does a 0.5 carat diamond ring look like?

A 0.5 carat round center is about 5 mm across, roughly the width of a pencil eraser, and sits comfortably within the width of most fingers. Ovals measure about 6 by 4 mm and look slightly larger from the top. On these rings the center can be set alone on a plain band or framed by a halo, pave or side accents of small lab-grown diamonds.