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Luminous Diamonds

MADE UNDER PRESSURE. We all face immense amount of pressures that is rarely seen by others. When you follow the light within, you transform that pressure into greatness. Natural diamonds were formed billions of years ago, deep under the surface of the earth. While forming, they absorbed trace amounts of various other elements which can cause fluorescence.

The world’s rarest diamonds look different in different lights. Under UV exposure, Luminous Diamonds® emit an unmistakable blue glow. Diamonds with very strong fluorescence are the rarest. Less than 6% of the diamonds submitted to AGS Laboratories have medium to very strong fluorescence, with less than .5% displaying very strong fluorescence. (AGS, Laboratories)

Luminous Diamonds® glow from within under UV exposure. Hidden in plain sight, they totally transform when exposed to UV light.

Stunning in sunlight. Luminous in UV light!


For over 40 years the Gumuchian women have been designing and manufacturing the most exquisite, versatile, timeless and perfectly executed jewelry. Each piece is brought to life in their Manhattan atelier, never using anything below platinum or 18kt gold. From this vision their “Designed by Women for Women” mantra emerged, setting out to embody the confidence and beauty of all women.


William Henry uses classic and unique materials with hand forged Damascus steel to create pocket knives with an old technique employed to design swords from 300BC to 1700AD. Their knives and pens are exquisitely crafted pieces of functional art.

Whitehouse brothers

Whitehouse Brothers’ creates new antique style engagement rings for the bride seeking a vintage look. These Edwardian style engagement rings are manufactured using a technique called the “die-struck” process, making them 33% more durable than the average ring.



Underwood’s is proud to present some of the most spectacular diamond engagement, colored stone and anniversary rings you will see anywhere. Rare and exquisite, every item is a one of a kind, featuring the finest quality diamonds meticulously set in handcrafted platinum or 18 karat gold. Each diamond is hand selected by one of our educated buyers and most designs are created by the company’s President, Clayton Bromberg. These are the finest pieces of jewelry you will find in Jacksonville and Ponte Vedra Beach, FL.


Tudor watches have a long history for quality and impeccable design at a great price. At Underwood’s, we are proud to have been one of the first official Tudor retailers when the brand was reintroduced in the United States in 2013. If you’re looking for a luxury watch with a vintage or throwback style, Tudor is a great way to go. Other designs suit discerning tastes.



Based in Tokyo, Japan, Suwa’s mission is to create jewelry that can be passed on from generation to generation. Underwood’s carries their timeless anniversary bands which feature diamonds, rubies, emeralds and sapphires.

Sydney Evan


Sydney Evan’s designs are inspired by anything and everything. The collection features fashionable beaded bracelets for layering and delicate 14kt. gold pieces of every variety.



Underwood’s carries unique, one of a kind colored gemstone jewelry designs by Spark Creations. This collection features gemstones such as sapphire, opal, zircon, tourmaline, tanzanite and more.


Founded in 1891 the Tavannes Watch Company has obtained over 300 patents for mechanical and automatic timepieces.  Many of these original innovations are still used in their watches today.  Tavannes Watch Company is known for its quality, accuracy, and value in the world of fine Swiss timepieces.



Seiko is a 130-year-old story of innovation.  From the very start Seiko’s credo was, “Seiko should always be a step ahead of the rest.”  Thanks to a continuous stream of industry leading revolutions over the decades, the company established, and has maintained its position as a world leader in the technology of time.  Seiko continues to push the boundaries of time with six different watchmaking technologies:  Mechanical, Quartz, Kinetic, Spring Drive, Solar, and GPS Solar.

Roberto Coin Cento Collection


Cento means one hundred in Italian and is Roberto Coin’s luxury diamond collection. Cento diamonds have 100 facets, instead of the standard 57 or 58 allowing it to be as unique as the woman it’s given to.

Roberto Coin

Roberto Coin is beautifully crafted gold jewelry designed and manufactured in Italy. Roberto Coin adds a signature ruby to each of his designs which touches the wearer’s skin and represents good fortune.”



Ritani is exclusive to Underwood’s in Jacksonville and Ponte Vedra Beach, FL. We carry a large selection of their diamond engagement rings and diamond wedding bands. All of Ritani’s rings are handcrafted in New York.

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