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Blogging into the future

November 7th, 2021 by Scott C.

While looking for some information on the website recently, I noticed that many of the old blog entries here had been truncated. The hosting for our site has changed many times over the years, and at some point data had been lost. Luckily, I do save our old backups so I was able to restore most of the missing information. While some of them date back as far as 2008, there is plenty of great information here that’s still relevant today.

These days we obviously aren’t doing many blog updates – the internet has moved on to Social Media posting instead. We do post regular updates to our Facebook and Instagram several times a week, so that’s a great way to keep up with us. There are also new inventory items being added to the website all the time!

Crank Up the Presses!

December 7th, 2019 by James L. Sweaney, CGA, FGA. GG
Facsimile image of the earrings

Recently, we examined an expensive pair of diamond earrings for a new client. She had purchased them from a local “Jewelry Mart” jeweler who provided this “appraisal.”

We easily identified the center diamonds as lab-grown diamonds. Each stone had the wording “Lab Grown” and an ID number laser etched on the girdle. Notice the “DESCRIPTION” supplied by the seller- the stones are not identified as lab-grown diamonds. While the color and clarity are about right, they are just labeled as “2 ROUND DIAMONDS EACH WEIGHT 1.03 CTS.”

The “APPRAISED VALUE” of $14,000 is about 2 1/2 times what she stated she actually paid for the earrings. We see a lot to these “Feel Good” documents– some sellers use them to convince the buyer of a super “deal.” Turns out the price she paid would be a high retail price for similar earrings with lab grown diamond centers.

In a recent Federal Trade Commission (FTC) ruling, the term “diamond”, when used by itself, should only refer to natural diamonds mined from the earth. For synthetic (man-made) diamonds, the stones should clearly designated in close proximity as “lab grown, cultured, cultivated, man made, etc.” so that the buyer knows what they are buying.

Sellers should disclose the facts about what they are selling, especially when it makes a big difference in the value of an item. The wholesale price (dealer to dealer price) of lab grown diamonds of this size and quality is currently about 30% that of natural diamonds mined from the earth. 1 ct H SI lab grown diamonds currently wholesale for ~ $1400 per carat in our local jewelry district. The Gem Guide price book lists well cut natural mined diamonds of this quality for $5020 per carat wholesale. Do the math!

According to one of our favorite diamond suppliers, producers are flooding the market with man made diamonds, causing substantial price drops. If you don’t think lab grown diamonds are being mass produced, check out these images from the factories in Asia that are making lab grown diamonds.

Presses for growing HPHT diamonds
Pressure cookers for growing CVD diamonds

He also said that some major manufacturers and department stores are using lab grown diamonds in their jewelry. And, now that lab grown diamonds are available in tiny sizes (down to 1 mm), some vendors are mixing lab grown melee into parcels of natural mined diamonds. This influx of lab grown diamond creates a tremendous problem for consumers as well as jewelers selling to the public.

For consumers, we advise asking good questions about a diamond you might buy. Because of the big difference in value, you can see it’s very important to know the origin of the diamond- whether its natural mined or lab grown.

For retailers, identifying lab grown diamonds, especially the tiny ones, is tedious and difficult without the proper equipment. Last year, Mardon made a substantial investment in the latest hi-tech device for identifying lab grown diamonds — see our blog “GIA iD100 Diamond Testing at Mardon Jewelers”, published March 3, 2018. We test any diamond jewelry that doesn’t look natural.

If you’d like more information about lab grown diamonds and colored stones, please give us a call or stop by the shop. One of our four gemologists will be happy to answer your questions.

We’re located in the Canyon Crest Towne Centre, enter from Central into the center parking lot.

Natural vs. Lab Grown Diamond

September 27th, 2019 by James L. Sweaney, CGA, FGA. GG

Today, consumers in the market for a diamond can choose between natural mined diamonds and lab grown diamonds. Lab grown diamonds, also known as synthetic diamonds, cultured diamonds, or cultivated diamonds are widely available. They are true diamonds in all but their origin — they are grown in laboratories instead of being mined from Mother Earth. Their physical properties, such as hardness, transparency, and ability to reflect light are essentially the same as the diamonds your grandmother wore. Their value is a different story.

A brief history of synthetic diamonds:

Diamond was first described scientifically as a crystalline form of carbon in 1797. As early as 1879, scientists were claiming to have synthesized diamond, but these efforts were debunked as not really diamond. It wasn’t until 1955 that scientists at General Electric were the first to synthesize diamond by a verifiable and repeatable method. Essentially, GE scientists copied the tremendous heat and pressure found in the molten magma of our Earth. Their results were true diamonds but very tiny ones– smaller than grains of sand.

Methods of synthesis:

Since then, major advances have been made in ways to synthesize diamond. One method called HPHT (High Pressure High Temperature) is along the lines of the GE discovery. Another technology is CVD (Chemical Vapor Deposition), often used in the semiconductor industry to produce thin films for computer circuitry. Both technologies can grow diamond crystals large enough to facet into polished diamonds for jewelry.

Today, over 30 manufacturers are producing lab grown diamonds for jewelry. Most of these producers are in China and India. Gem grade lab grown diamonds are available in a wide range of qualities in sizes up to 10 carats.

Marketing claims:

Synthetic diamonds are often marketed as “eco-friendly, sustainable, green, innocent, etc.” The pitch is basically that you can enjoy the beauty of the diamond without having a guilty conscience about buying a mined diamond. What many people don’t realize is that natural diamonds support the livelihood of 10 million people globally, including 1.5 million artisanal and small scale miners in Africa and South America.

The makers generally don’t disclose the large amounts of energy required to produce lab grown diamonds. Since carbon is cheap, the cost basis is the technology and the energy required to maintain the process. It’s estimated that on a per/carat basis, lab grown diamonds generate three times more carbon emissions than mined diamonds.

Value of lab grown diamonds:

All gems are valued based on beauty, durability and rarity. Besides their beauty and durability, natural diamonds are unique and rare. Natural diamonds of good quality and size will always have lasting value. They are billion year old precious gems that are older than life itself.

Consumers should know that prices for lab grown diamonds can drop precipitously. Lab grown materials are mass produced so they aren’t rare. As supply increases, unless demand grows, prices inevitably drop. And because they aren’t rare, they don’t have much resale value.

For example, around 2016, as production increased, the wholesale price for lab grown diamonds (~ 1 carat sizes) dropped 30%. Today, prices are about one third the value of a similar natural diamond. Now, a one carat round ideal cut lab grown diamond, graded E color, SI1, wholesales for ~ $2200 per carat, compared to ~$6000 per carat for a similar natural diamond.

We at Mardon Jewelers are committed to telling you the facts about the gems and jewelry we sell. We’re happy to provide lab grown diamonds, emeralds, rubies, sapphires and opals to clients who ask for them. Our gemologists take care to explain the relevant facts about lab grown gemstones.

Lab grown products offer beauty and wearability at a much lower price than natural gems, but they don’t have the intrinsic value of rare natural gems. For those who are looking for lasting value, whether as heirlooms or investments, natural gems are the choice to make.

More precious than Gold

June 14th, 2019 by James L. Sweaney, CGA, FGA. GG
Cloisonne Enameled Pendant, pure silver, 24K cloisonne wire, 14K bezel and setting, by Magick, a noted California artist/enamelist

Fine jewelry, made of precious metals and gems, can be very expensive. We often focus on the dollar value of the item rather than the real personal values conveyed by the jewel. Some things though, are more precious than gold.

We had a wonderful experience with a new client who purchased this fine cloisonne enameled 14K gold pendant. Vicky came into the store, began browsing thru our jewelry displays. She was admiring our collection of fine enamels by Magick, when she zeroed in on this Hummingbird pendant. She purchased it right away and then me told what it meant to her.

Her beloved sister, who died recently after battling cancer, had always loved hummingbirds. She fed them constantly with numerous feeders in her back yard. During the memorial service at the cemetery, while Vicky was eulogizing her lost sister, a hummingbird had flown down and hovered over the flowers on the casket. So now, Vicky wears a very special hummingbird next to her heart to remind her daily of her loved one. This hummingbird pendant can be passed down thru the generations of this family, beautiful in its own right, but completed by it’s intriguing story.

It requires high levels of skill, artistry and patience to create the heirloom quality you see in this pendant. Because they are made from precious metals and high quality enamels, enameled jewels like this will last as long as you take reasonable care of them.

Stop by to see our collection of fine enamels by Magick as well as the fine enameled pieced featured in our famous Riverside Raincross collection. We also have vintage enameled piece occasionally in our Estate Department.

Mardon is open 10 am to 5:30 pm, Tuesday thru Saturday. We’re located next to the Rite Aid drugstore in the Canyon Crest Shopping Centre. It’s easiest to find us by entering the centre thru the main entrance on Central Avenue. Our phone is 951 682-2325

Reader’s Choice 2019

May 2nd, 2019 by James L. Sweaney, CGA, FGA. GG
A Luscious Sapphire Engagement Ring with a Surround of Sparkling Diamonds

Once again, Mardon Jewelers is asking for your vote as the Inland Empire’s favorite jeweler. The Reader’s Choice survey by the Riverside Press Enterprise is a fun way for you to be involved in the businesses of your community. Your votes single out the best businesses and services available where you live.

Your opinions matter! Small businesses like Mardon Jewelers need the support of their community to be able to compete in today’s complex economy.

Just click this poster to vote. You can vote every day through June 2 — Obviously, the more often you vote, the better chance you’ll have win the $100 weekly prize.

One of our specialties is custom jewelry. We make custom jewelry from scratch– the secret ingredient is you! We listen to your wants and desires, your ideas and goals, then build them into your own personal masterpiece. Whether it’s a ring, pendant, earrings or bracelet, it will always be yours exclusively. Here are a few of our most recent custom jewels.

A Beautiful 2 carat Marquise Diamond Engagement Ring
Indicolite Tourmaline to the Max!

A Marquise Diamond Ring, accented with Sapphires, restyled – She loved it!

Vote online at this URL-

Voting ends June 1, so let your voice be heard. We’re counting on you!

Consumer Alert- Lab-Grown Diamond Ads

April 6th, 2019 by James L. Sweaney, CGA, FGA. GG

Custom engagement ring by Mardon, with a lab-grown diamond center flanked by natural diamonds

We have nothing against lab-grown diamonds, lab-grown emeralds, or any of the lab-grown stones available today. Although the focus of our gem business is for naturally occurring gemstones mined from the Earth, we sell lab-grown stones occasionally. For some consumers, they are a great choice — for example, we made a ring with a lab-grown diamond for an engineering student who was fascinated by the technology that produces these stones. Where cost is an issue, a fine lab-grown emerald, while not cheap, is about 1/10 the cost of a fine natural emerald from the mines of Colombia. The crucial thing is that you, as a consumer, know and understand what you are buying.

According to the April 5 issue of National Jeweler, a respected jewelry trade journal, the Federal Trade Commission recently sent letters to eight companies warning them that their ads for lab-grown diamond jewelry or diamond simulants (CZ, moissanite) could be deceptive.

Last year, the FTC overhauled the Jewelry Guides, its rulebook for the jewelry industry that outlines the terms marketers should and shouldn’t use to describe and sell jewelry to consumers. These guide lines clearly state the following. (excerpted from National Jeweler 10X Blog by Michelle Graff, April 5, 2019)

1. Importantly, according to the 2018 Guidelines, “when ‘diamond’ appears by itself, it can only refer to a natural diamond mined from the Earth.”

The big differences in value make these names and descriptions very important for consumers, so that they are truly aware of what they are purchasing. Currently, lab-grown diamonds sell for about 1/2 the price of natural diamonds. If trends match what we’ve seen with natural emerald versus lab-grown emerald and other natural gems vs. their lab-grown counterparts, lab-grown diamonds will sell in the future for 1/10 the price of mined diamonds.

This just makes sense. Natural mined gems are rare gifts of nature, available only in limited supply, especially in larger sizes and finer qualities. These diamonds are valued based on their rarity, as well as their beauty and durability.

Lab-grown stones can be produced in large quantity, so rarity is not a factor. With prices for lab-grown diamonds at their current level, producers are scrambling to cash in. The supply of lab-grown diamonds will inevitably exceed demand, with consequent price drops.

Consumers who pay thousands of dollars per carat for lab-grown diamonds today may be dismayed to find the same product available in a few years for hundreds of dollars per carat.

2. If a product is a lab-grown diamond, the the fact that it is man-made must be clearly and conspicuously stated.

FTC recommends these man-made products be described as laboratory-grown, laboratory-created, or (manufacturer name)-created, and these terms must be “immediately accompanied, with equal conspicuousness” by one of these terms: it cannot stand alone. The term cultured must meet the same standard.

FTC staff found that “some businesses only put information on how a stone was really made on a ‘diamond education’ webpage, rather than in or near an ad where shoppers were more likely to see it.”

On some social media sites, using a hashtag for this disclosure isn’t adequate — e.g. #labgrown may not meet the “clear and conspicuous” guideline. FTC researchers also found instances on social media where hashtags such as #diamond might imply that a lab-grown diamond is the same as a mined diamond.

3. CZ and moissanite aren’t the same thing as diamond, and that must be clear too.

Ads for these products, properly referred to as simulated or imitation diamonds, must avoid describing the products in a way that “falsely implies” what they are selling has the same optical, physical and chemical properties as mined or lab-grown diamonds.

The physical hardness, transparency, and optics of natural and lab-grown diamonds are what make them so beautiful, sparkly and durable. CZ and moissanite don’t match these properties, so they can never look the same and won’t stand up to wear in the same way.

4. “Eco” claims, such as “eco-friendly, eco-conscious, or sustainable” shouldn’t be used without explaining exactly what they mean.

“Eco” consciousness and the related concepts of “sustainability and ethical sourcing” have become important considerations for many consumers about the things they purchase and consume. It’s too easy for marketers to cross the line with unsubstantiated claims to take advantage these legitimate concerns.

For example, if a company is claiming it’s product is “eco-friendly” because it’s recyclable or uses less resources, or that it’s “green” because it is “carbon neutral,” the FTC says ads should contain publicly available and/or scientific evidence backing up these claims.

While the FTC release did not name names, the April 3 edition of the New York Post singled out Leonardo DiCaprio-backed company, the Diamond Foundry as one of the recipients of the above mentioned letters. According to the Post, the FTC expressed concerns in it’s letter to the Diamond Foundry.

Cardinal Point Setting

March 29th, 2019 by James L. Sweaney, CGA, FGA. GG


Introducing the Cardinal Point Setting, a new concept in ring design. Rather than having prongs positioned at the traditional spots at the corners, we’ve set the stone with the prongs at cardinal points of the compass,  North, West, South and East. This has several benefits. The open design is clean and modern, yet with a flavor of the Art Deco period. It allows you to clean the back of the stone more easily. The cardinal point prongs will protect the stone from the wear and tear of everyday life. We think this design really shows off the stone because you see its color and shape more clearly.

This ring (stock # I-28817) features a beautiful 3.86 carat oval Aquamarine. This is a vintage gemstone acquired in a group of estate pieces we purchased. Its superb blue color is referred to in the gem trade as “Santa Maria.” The mine at Santa Maria de Itabira, a town in the state of Minas Gerais, Brazil, produced some of the best quality Aquamarine the world has seen. Natural inclusions give this Aquamarine a pleasantly soft look. Sadly, this mine isn’t producing any more.

We’ve cast this ring in 14K rose gold– the warm coppery color of this gold alloy is a perfect complement to the cool blue of the aqua. We’ve added a touch of hand engraving along the underbezel– a subtle touch just for you!

Look for more Cardinal Point Settings in the future. If you own a gemstone you’d like to be wearing or have a special gem you’ve been wishing for, consider this new style– it’s great for most shapes, especially oval, marquise, round, and emerald cuts. Our custom design department is ready, willing and able to help you find the perfect gem and design the ring of your dreams!

Arts and Crafts Repousse Brooch

January 5th, 2019 by James L. Sweaney, CGA, FGA. GG

Arts and Crafts Repousse Brooch of 14K gold, natural pearls, and black onyx.

This unusual antique Arts and Crafts gold brooch is now on display at Mardon Jewelers. Made circa 1900 or so, the piece shows the classic handcrafted elements of the Art and Crafts movement.

The craftsman began by drawing the design on paper, then either glued the design onto a sheet of 14K yellow gold or drew the design directly on the gold with india ink. The gold was then pierced with a jeweler’s saw to create the openings in the design and trimmed to the design outline.

The pierced sheet was then placed on a heavy pitch bowl. In the repousse method, the pitch in warmed just enough so that the work can be embedded firmly. The pitch is slightly pliable and supports the work while it’s being shaped with steel punches. The hemispheric shape of the bowl allows the work to move easily to follow the craftsman’s tools.

Pitch bowl, base, steel punches and chasing hammer. Photo courtesy Creatstudio.Co.UK

First, the piece was worked on the reverse side using steel punches and hammer to develop raised reliefs and the lovely three dimensional shape.

Warming the pitch again allowed the work to be turned over so the front could be tooled. The details of the front including the grape leaves and the over/under elements were hammered into the gold using various punches. The punch marks made a distinctive texture that enhances the hand wrought look. The finished gold item was bathed in chemicals several times to develop a bloomed gold surface. Bloomed gold is explained on this Mardon blog post, ?

The bezel set black onyx center, which is actually dyed black chalcedony, has holes that were drilled so the grape leaf and pearl cluster could be attached. The grape leaf, also made with the repousse technique, was fired with opalescent enamel.

Opalescent enamels, so very popular in the late 1800’s, were made by mixing a small amount of opaque enamel powders with transparent enamel powders which were then fired (melted) onto the surface of the gold. Opalescent enamels were usually etched slightly with acids to create a matte surface, creating a lovely velvety look.

The Arts and Crafts movement rejected the mechanization of the Industrial Revolution and espoused the virtues of the individual craftsman. Rather than any particular style, Arts and Crafts designers cared more about excellence of design and fine hand craftsmanship. The floral elements of grape leaves and grapes, the warm bloomed gold and matte finished enamel of this brooch are very typical of the jewelry of the Late Victorian and Art Nouveau era.

You can tell by the slightly irregular shapes and openings that the work was done using hand tools. The design, meant to be symmetrical, is very slightly skewed as you might expect from something done by the human eye.

This brooch may have been a graduation or bridal gift because the grapes were symbolic of prosperity, fruitful unions, and abundance. We certainly know this piece was well loved because some of the enamel has chipped, an indication of substantial wear.

The brooch is unusual for an Arts and Crafts jewel in that it’s made of gold– Arts and Crafts jewelers were more concerned with the craftsmanship and design of their work than the value. Most jewels of this style were made of silver or copper rather than gold, so that’s why we consider it to be quite rare.

This antique jewel and others are waiting to share their stories with you at our estate department at Mardon. Stop by during our regular business hours Tuesday thru Saturday, 10:00 to 5:30. We’re located at the Canyon Crest Shopping Centre, 5225 Canyon Crest Drive, Riverside. Enter the central parking lot from the Central Avenue entrance and you’ll see us just left of the RiteAid drug store.

Please keep us in mind if you have jewelry to sell– we’re always interested in buying  antique and vintage jewelry. Call for an appointment if you have things you’d like to sell or have us appraise.

Vintage Pop-out Coin Pendant

December 9th, 2018 by James L. Sweaney, CGA, FGA. GG

Repousse Morgan Silver Dollar with Miss Liberty

Repousse coins, also known as pop-out coins, are a novelty item made from actual minted coins. The process to make these was first patented in the US in 1902. Coins as small as a dime have been “popped-out.” Various presidents and celebrities have been memorialized this way, but the most popular subject has always been “Miss Liberty”.

This particular one was made from a 1921 Morgan Silver Dollar. It is set in a 14K yellow gold bezel that’s encircled by 24 Akoya cultured pearls.

Repousse is a traditional jewelry making technique where flat metal is worked from the reverse side into relief (3D) designs. This piece was created with hub and die method.

Master Hub on the left, Master Die on the right

A hub has a positive or relief (raised) image of a design on the end of a steel rod. The hub begins as a plaster sculpture about 8 to 12 inches in diameter, from which a Master Hub is created in steel. A special process reduces the image to the actual size needed and carves it into the steel. The Master Hub, which bears the relief image of the design, is then copied onto a Master Die (which bears the negative or sunken image of the design).

This silver dollar was pressed into the Master Die with a steel tool pushing from the back, using a press that can generate over 10,000 pounds per square inch of pressure!

Reverse view, showing tool impression

You can see from this side view just how far the silver is “popped out”– in this case, almost 1/2 inch!

Side View

This particular piece is beautifully sculpted. Miss Liberty’s gaze seems to follow you as you view the piece from side to side. She’s truly a masterpiece of the tool and die maker’s art!




45 degree view from left

45 degree view from right

How many individuals has this serene face greeted? We should thank our friends in France again for this beautiful lady– she’s a shining symbol of our American way of life!

You’ll be able to see Miss Liberty in the estate department along with many other interesting and unusual vintage items at Mardon Jewelers, Canyon Crest Towne Centre, 5225 Canyon Crest Dr, Riverside, CA, 92507. Enter the main parking lot on Central–we’re the first shop to the left of the Rite Aid drugstore in the center parking lot. We’re open 7 days a week from now til Christmas, 10 – 5:30 Sunday thru Thursday, 10 – 8 Friday and Saturday.

Mission Belle Memorial Trip

November 9th, 2018 by James L. Sweaney, CGA, FGA. GG

Dutch children at the Mission Bell memorial, along the River Lek, Holland

On a recent trip to Holland, we participated in the unveiling of a memorial to the Mission Belle, an American B17G that was shot down near Rotterdam on December 1, 1943 after a mission to bomb war materials factories in Germany.

The Mission Belle was part of the famous 8th Air Force. Half the U.S. Army Air Force’s casualties in WWII were suffered by the valiant 8th– 26,000 dead, 47,000 wounded. Eighth Air Force personnel were awarded 17 Medals of Honor, as well as 220 Distinguished Service Crosses, 442,000 Air Medals and of course, numerous Purple Hearts.

The people of the Netherlands suffered grievously during WWII. Many ferocious battles were fought over and on Dutch and Belgian soil. Toward the end of the war, the Nazis confiscated all the available food so that the Dutch were starving. Allied airlifts of food saved many lives. The Dutch have not forgotten.

The memorial to the Mission Belle was created by the people living near the crash site. The good folk of these small villages including Lekkerkerk and Neiw-Lekkerland banded together to pay for and build the monument.

We were invited to the unveiling because my father was the copilot who crash landed the badly shot up B-17 in the River Lek. Two drowned in the crash while Dad and six others survived. The tail gunner had been killed in the battle to shoot down the plane. All the surviving crew were then captured by the Nazis and became prisoners of war. My dad survived 18 months in Stalag Luft 1, near Barth, Germany. The other 6 Americans also spent the rest of the war in prison camp and lived to tell their stories.

The ceremonies leading up to and the actual unveiling of this monument to the crew of the Mission Belle were simply amazing. Needless to say, we and the other family members of the crew were treated like royalty– all 36 of us! Prior to the ceremony, a group of WWII re-enactors, dressed in period uniforms, recreated the actual briefing for the final flight of the Mission Belle. We were driven to the monument in WWII Jeeps and Trucks where we were greeted by a large cheering crowd!

Band of Brothers re-enactors

Army trucks leaving the memorial

The day after the unveiling, we visited the cemeteries where the 3 who died are buried, two at the Netherlands American Cemetery at Margraten, Netherlands, the other at the Ardenne American Cemetery in Belgium.

Netherlands American Cemetery, Margraten, Holland

Ardenne American Cemetery, Belgium

Our experience was an eye opener. What really struck home and warmed our hearts was how appreciative the Dutch still are of the thousands of Americans who fought and died liberating their country. Thanks to our guys, they have had 75 years of peace. The Dutch take their children to these monuments and teach them that there is a price to pay for freedom. In their words, freedom is not a given thing.

On this Veterans Day, Sunday, November 11, please take a moment to reflect on your life, how many good things you enjoy and especially, your own personal freedom – give all of our brave veterans, living and dead, a salute.