Historic Diamonds
Rare Natural Diamonds Lead Phillips Auction This June
By Grant Mobley. May 29, 2025
The New York City townhome offers sumptuous decor, a cozy vibe and plenty of diamonds.
Jean Schlumberger ‘Etoile de Mer’ brooch (Courtesy of Phillips Auction House)
Phillips Auction House’s New York Jewels auction, scheduled for June 12, will become one of the year’s most talked about events for fine jewelry collectors and natural diamond investors. The auction presents 105 expertly selected lots that highlight design excellence and craftsmanship, including vibrant fancy color diamonds and Muzo Colombian emeralds, alongside timeless creations from renowned brands such as Tiffany & Co., Van Cleef & Arpels, Bulgari, Chaumet, and others. For those who follow the fine jewelry market closely, this sale reinforces the enduring luxurious status of these precious assets.
Below, we spotlight nine standout pieces that exemplify the rarity, artistry, and investment potential that define this landmark auction.
Meet the Expert
- Grant Mobley is the Jewelry & Watch Editor of Only Natural Diamonds.
- He is a GIA Diamonds Graduate.
- He has over 17 years of jewelry industry experience, starting with growing up in his family’s retail jewelry stores.
Phillips Auction: Fancy Color Diamonds Steal the Spotlight
Phillips Auction House’s New York Jewels auction features a radiant cut fancy intense pink diamond weighing 3.03 carats, with an estimated value between $1.2 million and $1.6 million, as its main attraction. The rare color designation of this pink diamond makes it both visually breathtaking and highly sought after by collectors. The value of such high-quality fancy pink diamonds continues to escalate as collectors pursue these rare, naturally formed wonders that become increasingly difficult to find.
Joining the pink diamond is an oval shaped fancy vivid yellow diamond weighing 4.43 carats, with an estimated value of $75,000 to $125,000. Yellow diamonds achieve their most coveted status when graded as fancy vivid, representing their peak levels of saturation and brightness. Despite lab-grown attempts to replicate natural color, these unaltered treasures capture collectors’ imaginations and remain unmatched in prestige and value.
A colorless emerald cut diamond ring weighing 6.03 carats, with VVS1 clarity and F color, is a significant find valued between $90,000 and $150,000. This gem exhibits exceptional purity and brilliance, appealing to purists who value precision-cut beauty in its ultimate, timeless form.
Phillips Auction: Natural Gemstones Elevate the Offerings
The diamonds stand as a major attraction, but the Phillips Auction House’s New York Jewels auction boosts this draw by adding an array of stunning natural colored gemstones to the sale. Two exceptional Colombian emerald and diamond rings represent the auction’s highest echelon.
A 13.36-carat step-cut Colombian emerald ring, estimated between $300,000 and $500,000, has been certified by five major gem labs, including SSEF, GRS, and Gubelin. This emerald stands out for being completely untreated for clarity and color, which is uncommon even among premium natural emeralds.
The 10.60-carat emerald and diamond ring, treated with minor oil and estimated at $90,000 to $120,000, underscores the enduring market demand for natural Colombian gems that combine pedigree and beauty.
Both emeralds display vibrant green hues and are directly connected to the famed Muzo mine, which is renowned globally for its exceptional finds of unmatched color and quality.
The Phillips Auction House’s New York Jewels auction has also included a 3.91-carat no-heat Burmese ruby ring, estimated at $80,000 to $100,000, and an 8.03-carat unheated Ceylon sapphire ring, recognized as “Royal Blue” by GRS, estimated at $70,000 to $90,000. Gemstones without artificial treatments that exhibit top color reflect the importance of natural scarcity and gemological authenticity.
Phillips Auction: Signed Jewels
Alongside these exceptional natural stones, the auction is rich in diamond jewelry crafted by the world’s most respected maisons. The Folie des Prés high jewelry necklace from Van Cleef & Arpels includes approximately 24 carats of diamonds set in 18k white gold. The natural diamonds in this piece form a refined interpretation of wildflowers.
A matching Van Cleef & Arpels Galuchat diamond bangle, featuring up to 19 carats of diamonds, displays a shagreen-inspired texture and is estimated at $40,000 to $60,000. These pieces serve as wearable art that defines the essence of haute joaillerie for collectors.
Tiffany & Co. also features prominently in the auction with an exceptional Etoile de Mer brooch by Jean Schlumberger, estimated at $80,000 to $120,000. Adorned with diamonds, sapphires, and tsavorites, the brooch has renewed cultural significance through its connection to the 2025 “Sea of Wonder” Blue Book collection, which draws inspiration from marine motifs.
Phillips Auction: Why This Sale Matters
Natural diamonds are geological miracles, formed over billions of years under intense pressure before becoming remarkably rare discoveries. The June auction at Phillips offers collectors the opportunity to acquire the rarest of these wonders and connect with their enduring beauty and value.
The New York Jewels sale is a tribute to everlasting luxury, featuring stunning natural-colored diamonds, majestic emeralds, and signed pieces of jewelry art.
Visit Phillips’ New York gallery to preview the full sale from June 8 to 11. The live auction begins at 10 a.m. EDT on June 12.
