A 6 mm dome band with a bezel-set marquise lab-grown alexandrite at the center, flanked by two pavé crescent moons and closed by a four-point star on each shoulder. The stone shifts between teal-blue and violet as the light changes. Solid 925 sterling silver finished in black ruthenium, polished, standard fit. Sizes 7 to 13.
Lab-Grown Alexandrite
Visible Color Shift
Bezel-Set Marquise
Crescent Moons & Stars
6 mm Dome Profile
Black Ruthenium Finish
Three Ways to Wear It
As a wedding band: a 6 mm dome is the most-worn width in this range, substantial without being heavy, and low enough to sit under a glove or a watch cuff. As an engagement ring: the bezel-set marquise gives it a real focal point that most plain bands do not have. And by anyone: nothing about the design is gendered. On a smaller hand the 6 mm reads bold rather than masculine.
A 6 mm width is most often searched as a men's band, and that is where you will find this ring shelved in our collections, but it is genuinely unisex. If you are weighing widths, our wedding band width guide is the place to start, and how to choose a men's engagement ring covers the newer half of the question.
Moons and Stars
This is the Nightbriar celestial vocabulary cut down to band scale. Two crescent moons face the center stone, each pavé-set and edged in milgrain beading, with a four-point star sitting further out on each shoulder. On a black ruthenium ground the moons and stars sit lit against a dark sky rather than on a bright one.
It is finished in the same black ruthenium as the Nightbriar lab-grown alexandrite bridal set, so the two stack as an exact match: same stone, same motif, same metal. The same band is also made with a lab-grown ruby in black ruthenium and with gray moissanite in sterling silver; use the swatches on this page to switch between them. See the rest of the family in our black ruthenium jewelry and black rings collections.
The Alexandrite and Its Color Shift
Alexandrite is the stone that changes color. Under daylight it reads teal to blue-green; under warm indoor light or candlelight it swings to violet and plum. The effect is real optics: the mineral absorbs light unevenly across the spectrum, so what you see depends on what is lighting it. The shift is fully visible here, because the stone is faceted and open on top. Our piece on whether synthetic alexandrite changes color explains the mechanism.
This stone is lab-grown, with the same chrysoberyl chemistry and the same 8.5 on the Mohs scale as mined alexandrite. Our comparison of lab-grown versus natural alexandrite lays out the trade-offs. It is bezel-set: the metal wraps the girdle completely rather than gripping it with prongs, so on a band worn hard nothing catches and there are no prongs to wear down. The marquise sits north–south, as our guide to marquise cuts explains.
Metal and Fit
Solid 925 sterling silver underneath, finished in black ruthenium. Ruthenium is a platinum-group metal, the same family as rhodium and platinum, and it is the harder of the two common black finishes. It settles to a deep gunmetal rather than a tinted gray, and it holds that color under daily wear.
The profile is a dome: rounded on the outside, flat on the inside, in a standard fit. If you are used to comfort-fit bands, order your true size rather than sizing down. Part of our men's rings, women's wedding bands and alexandrite wedding bands collections. Alexandrite is a June birthstone; see our birthstone guide.
Specifications
-
Width: 6 mm
-
Profile: Dome, standard fit, polished
-
Center stone: Lab-grown alexandrite, marquise cut, bezel-set, north–south
-
Color shift: Teal-blue in daylight to violet in warm light
-
Accent stones: Cubic zirconia pavé in the crescents and stars
-
Metal: Solid 925 sterling silver, black ruthenium finish
-
Design: Crescent moons and four-point stars with milgrain edging
-
Hardness: 8.5 on the Mohs scale (alexandrite)
-
Sizes: 7 to 13, including half sizes
-
Engraving: Available, up to 16 characters
-
Presentation: Free luxury velvet jewelry box
Care
Alexandrite is 8.5 on the Mohs scale and well suited to daily wear. Clean with warm water, mild soap and a soft brush, paying attention to the pavé where skin oils collect, then dry with a soft cloth. Avoid abrasive polishes and silver polishing cloths, which thin a dark finish, and keep the ring out of chlorinated water. Never use an ultrasonic cleaner.
Frequently Asked Questions
Is this a men's ring or a women's ring?
Either. Nothing about the design is gendered. A 6 mm width is most commonly worn by men, which is why you will also find it in our men's collections, but it works equally as a women's wedding band or as an engagement ring for anyone.
Does it match the Nightbriar alexandrite bridal set?
Yes, exactly. Same lab-grown alexandrite, same celestial motif, and the same black ruthenium finish, so they stack as a matched pair.
Does the color shift actually show?
Yes. The stone is faceted and open on top, so light passes through it and the shift is clearly visible: teal-blue in daylight, violet under warm indoor light.
Is the alexandrite real?
Yes. It is genuine alexandrite, a chrysoberyl, lab-grown rather than mined. Same chemistry, same hardness, same color-change behavior.
What is black ruthenium?
Ruthenium is a platinum-group metal, the same family as rhodium and platinum. As a black finish it is harder and holds its color better than black rhodium, and it settles to a deep gunmetal rather than a tinted gray.
Will the black finish wear off?
Not with normal wear. Ruthenium is hard and bonds well to sterling silver. Like any finish it can thin after years of daily contact, so keep it away from chlorine and abrasive polishes, and we can refinish the ring if it ever needs it.
Are the pavé stones diamonds?
No. The small stones in the crescents and stars are cubic zirconia. Moissanite or lab-grown diamond accents are available as a custom order.
What does bezel-set mean?
The metal wraps around the whole girdle of the stone instead of holding it with prongs, so nothing snags on fabric and there are no prongs to wear thin.
Is it standard fit or comfort fit?
Standard fit, flat on the inside. If you normally wear comfort-fit bands, order your true measured size rather than sizing down.
Is alexandrite a birthstone?
Yes. Alexandrite is one of the June birthstones, alongside pearl and moonstone.
What is it made of?
Solid 925 sterling silver throughout, with a black ruthenium finish. No brass or base metal.
Are the stones ethically sourced?
Yes. All Aquamarise stones are conflict-free and responsibly sourced, and every order arrives in a free luxury velvet jewelry box.
