Natural Diamonds
Fortuna & Co. · Natural Diamond Collection
Formed by the earth.
Chosen by you.
Search our live collection of GIA-certified natural diamonds, held exclusively in the USA, each with its own photo and 360° video. Each stone is reviewed by our GIA Graduate Gemologist before it reaches you.
13,000+ diamonds in stock · updated daily at 11:30 AM PT
GIA certifiedEvery diamond graded by the Gemological Institute of America.
USA-based diamonds onlyEvery diamond in this collection is held in the United States.
Reviewed by a GIA G.G.Personally checked by our GIA Graduate Gemologist before you commit.
Set by hand in ArcadiaPair any diamond with a custom setting made in our atelier.
The live collection
Find your diamond
Price
Carat
Color
ColorlessFaint
Clarity
FlawlessIncluded
GIA cut (round)
Applies to round brilliants
Fortuna cut score
All shapes · scored on the Fortuna Ideal
Diamond location
U.S. inventory only
Viewing
Polish
Symmetry
Table %
Depth %
Length to width
Something specific?
Tell us the diamond you have in mind and our gemologist will find it for you, often within a day.
Text (626) 888-1355All prices exclude sales tax, shipping and insurance. Every diamond is natural and GIA certified.
U.S. inventory: only diamonds currently held in the United States are included in this collection.
The Fortuna Ideal
An ideal cut, held to a higher standard.
Most jewelers call a diamond "ideal" if it falls inside wide, widely published proportion charts. The Fortuna Ideal is deliberately narrower. Our cut score out of 10 shows how close each diamond comes to it, so you can see at a glance which stones are truly exceptional.
I
Why we hold a stricter line
We are a manufacturer of fine and high jewelry, serving houses including Bvlgari, Buccellati, Damiani and Crivelli, and the House of Musy, the aristocratic jewelry house to the House of Savoy, Italy's former royal family. Our work for Italian high jewelry has taught us that in the finest pieces, a few tenths of a degree change how a diamond performs.
II
Judged by a GIA Graduate Gemologist
Our ranges were set, and every stone is reviewed, by our certified GIA Graduate Gemologist. A grading report tells you a diamond's grades; our gemologist looks at how it actually returns light, its fire, and the details a certificate can't show.
III
Tighter than the published ideal
For a round brilliant, common ideal charts accept a 54–57% table, 59–62.6% depth, a 34–35° crown and a 40.6–41° pavilion. The Fortuna Ideal asks for a 55–57% table, 60.5–62.2% depth, a 34.2–35.0° crown and a 40.7–40.9° pavilion, the narrow window where brilliance, fire and scintillation are most balanced.
IV
Every shape, its own ideal
Fancy shapes are scored on depth, table, length-to-width ratio, polish and symmetry, with ranges narrower than industry norms, such as an oval at 59–62% depth and a 1.38–1.48 ratio. Strong fluorescence lowers the score slightly. The cut score is our own assessment, not a GIA grade.
9.5+ Exceptional9.0+ Excellent8.0+ Very good7.0+ Good6.0+ Fair
Our promise
Every diamond, seen through a gemologist's loupe.
The grading report is only the beginning. Before any diamond leaves our atelier, our GIA Graduate Gemologist reviews it in person for brilliance, fire, and the small details a certificate can't show.
- GIA report you can verify online for every stone
- Diamonds held exclusively in the USA, with each stone's location shown clearly
- Fully insured delivery, or pick up at our Arcadia showroom
- Honest guidance, with no pressure to buy
Bespoke settings
From loose stone to the ring you'll wear forever.
Choose a classic solitaire, a halo, or a three-stone setting, or design something that is completely your own. We make each setting by hand in platinum or 14k and 18k gold, and our bench jewelers set your diamond in Arcadia.
- Solitaire, pavé, hidden halo, three-stone, and bezel settings
- Platinum, 14k or 18k yellow, white, and rose gold
- Personal design consultation, in store or by video
A gemologist's guide
Understanding the four Cs
Natural diamonds formed deep in the earth over a billion years ago. Every one in this collection is graded by GIA, the laboratory that created the four Cs, so you can compare stones with confidence.
I
Cut
Cut has the biggest effect on sparkle. For round diamonds, choose Ideal or Excellent so light returns through the top of the stone.
II
Color
D to F are colorless; G and H look white to the eye, especially in yellow or rose gold. Warmer K to M colors bring a vintage glow at a gentler price.
III
Clarity
Many stones from VVS1 to SI2 can be eye-clean. We review SI stones ourselves, and you can filter for eye-clean diamonds, so you never see an inclusion in the finished ring.
IV
Carat
Carat is weight, not size. Compare the millimeter measurements; a well-cut 1.50 ct can look larger than a deep 1.70 ct.
Questions
Before you choose
Are these natural, earth-mined diamonds?
Yes. Every diamond on this page is natural and earth-mined, with a GIA grading report you can verify online. We do not mix lab grown stones into this collection.
Is the inventory really live?
Yes. Our collection syncs with our diamond partners every day at 11:30 AM Pacific and shows GIA-certified stones currently held in the USA only. Diamonds sell quickly, so when you reserve one we confirm it is still available before taking payment.
How does reserving a diamond work?
Choose "Reserve this diamond" and send us your details. A gemologist will reply within one business day to confirm availability, answer questions, and arrange payment and delivery. Reserving is free and you are not committed to buy.
How quickly will I receive my diamond?
Diamonds held in the USA usually reach our Arcadia atelier within 2 to 4 business days. A custom setting adds about 2 to 3 weeks. Every delivery is fully insured.
Can I see the diamond before buying?
Yes. Every diamond includes a photo and 360° video, and you are welcome to visit our showroom at 125 S 1st Ave, Arcadia, to see your diamond under the loupe with our gemologist.
Do prices include the setting?
Prices are for the loose, GIA-certified diamond and exclude sales tax, shipping and insurance. Settings are quoted separately according to your design, metal, and size.
Fortuna & Co. · Arcadia, California
Let us find your diamond.
Share your budget and what you love. Our gemologist will send a personal shortlist from the live collection, with photos and video.
Prices are in U.S. dollars for loose natural diamonds, exclude sales tax, shipping and insurance, and may change as inventory refreshes daily. Availability is confirmed at reservation. Diamond images and 360° videos come from the grading and imaging process; actual appearance may vary slightly. Reports are issued by GIA (Gemological Institute of America). Inventory last refreshed recently.