From a Rubber Mold to a Finished Piece of Pearl Jewelry

The majority of the jewelry you see in the retail market is made using rubber molds. A rubber mold is what jewelers and jewelry manufacturers usually use to duplicate a piece of jewelry. The original piece of jewelry that is to be duplicated, would have been carved by hand, or created using computer-aided design (CAD) software and computer-aided manufacturing (CAM), like a 3D wax printer. We are proud to be able to say that the vast majority of Pearl Paradise’s jewelry (if not all), was originally carved by hand. There is a tangible difference between jewelry that is hand-carved by an artisan, and jewelry that is created on a computer by a technician. While hand-carved jewelry may not be mathematically perfect, the contours tend to feel softer and more fluid, while jewelry created using a computer seems to have a cold and more mechanical feel to it.

My name is John, and I started hand-carving wax models for jewelry, casting and making rubber molds 20 years ago. Over the years, I’ve created an extensive assortment of designs that I’ve captured and added to my rubber mold collection. When I joined Pearl Paradise, I brought over 3000 rubber molds with me. Today, on a daily basis, Hisano and I go through these rubber molds to hand-select which designs can be modified, if needed, to hold a pearl to add to Pearl Paradise’s online collection. After we select a design which we want to add to the collection, and make any necessary alterations, we then begin the process of creating jewelry from a rubber mold.

Above is a typical rubber mold. It was made with a device called a vulcanizer, which compresses and heats several layers of a special type of soft rubber, inside of which, the piece of jewelry you want to recreate is placed. The compressing effect of the vulcanizer squeezes the rubber around and into the crevices of the jewelry, capturing all of its details. The heating first makes the rubber soft, allowing it to flow seamlessly around the jewelry, and then the heat vulcanizes the mold rubber, making it firm. The mold is then hand-cut open to remove the original piece of jewelry. What is left is a three dimensional impression, ready for wax to be injected.

Step One: Injecting wax into the rubber mold.

Doing this step correctly is crucial to having your finished piece of turn out properly. The two key factors are wax temperature and air pressure. If the wax isn’t heated to an adequate temperature, it won’t flow correctly and will not completely fill the rubber mold. If the wax is too hot, it can create air bubbles, which result in your finished piece having porosity.

The melted wax inside of the wax injector is pressurized to force it into the rubber mold. If the pressure is too low, the liquid wax will not flow correctly and will not completely fill the rubber mold, similar to when the wax is too cold. [This is shown with the wax on the left.]

Conversely, if the air pressure is too high, it could result in visible mold lines and/or “flashing”. Flashing is when wax overflows the rubber mold’s design, resulting in extra wax on the injected wax model. [This is shown with the wax in the middle.]

When all of the variables are correct, the result is an injected wax model that is an exact duplicate of the original piece of jewelry. [This is shown with the wax on the right.]

Step Two: Sprue and invest the wax model.

In the photos of the wax injections, you can see a wax stick attached to the jewelry model. This is what is called the sprue. The sprue is basically the pathway for the liquid wax to get from the outside of the rubber mold, to the impression of the jewelry design in the center. Casting the piece in gold or silver is essentially the same process, but with different materials. Instead of injecting liquid wax into a rubber mold, you pour molten gold or silver into a plaster mold.

The first step in this part of the process is to attach the sprue of the wax model onto a rubber sprue-base.

You then slide a metal cylinder, referred to as a flask, over your wax model and onto the sprue-base forming a tight seal.

The next step is to mix a very fine plaster, called investment, and pour it into the flask. Before and after you pour the mixed investment, you have to put the mixture into a vacuum chamber which pulls all of the tiny air bubbles out of the mixture, and off of the wax model. If you left the bubbles in the investment mixture, your casting would have tiny metal bubbles attached to it where the bubbles were touching the wax model.

After the plaster solidifies, you gently pull off the rubber sprue-base, giving you access to the end of the sprue.

Step Three: Casting the piece of jewelry.

You’re now ready to put the flask into the casting furnace to harden the plaster and “burn out” the wax model, leaving an empty cavity that is the exact shape of the wax model. After all of the wax has burned out, and while the flask is still hot (between 800-1200 degrees Fahrenheit -depending on the metal and the design), you pour in your molten gold or silver into the hole where the end of the sprue was once visible. You always have to pour more metal than you need for the piece of jewelry you are casting. This is because the extra metal pushes the primary metal into the empty cavity where the wax model was, filling all of the fine details completely. The glowing metal you can see in the photo is referred to as the “button”.

Step Four: Cleaning and polishing the casting

After the flask cools for a little while, you submerge it in water, or “quench” it. This rapid cooling hardens the metal making it more durable and easier to work with. The rapid cooling also makes the plaster break away from the cast piece of jewelry in the center, referred to as the casting. After you clean off any remaining plaster, you cut your casting off of the metal sprue. If done correctly, your casting will have the exact same shape as your original wax model.

Your casting is now ready to be tumbled clean, then filed and sanded into shape.  Your next step would be to solder together the components if needed, in my case, the bezel and post are attached to the top of the pendant with the jump-ring. After the piece is assembled, you would then set the diamond. Finally, the piece is ready to be polished.

Not done yet! Now my favorite part… Selecting the pearl!!!

Step Five: Setting the pearl.

After the pearl is selected, it is drilled and attached to the mounting and …

 

We are currently creating a minimum of 12 new pearl pieces per month, one of which is posted weekly on Facebook for our “First Look Friday” promotion – One New Pearl Jewelry Design a Week.

I really hope you all enjoy the new pieces as they are produced!

The real art of making Tahitian pearl strands

A loose lot of undrilled Tahitian pearls

As I blogged about in June of this year, there are two ways pearl dealers are able to source Tahitian and South sea pearls; either in finished strands or loose pearl lots. When selecting finished strands, dealers purchase just what they need without making a large investment or having to work with the pearls … and pay a hefty premium. When dealers purchase lots, they have to separate, grade, match and drill in order to create strands.

Since 2007, we almost exclusively purchase loose lots to create our Tahitian strands and jewelry from scratch. The primary reason is we prefer to use  ”A/B lots.” These lots are a mix of pearls that have one to zero spots that drill and set clean or set clean face up – very close to perfect . It’s nearly impossible to find finished strands like this from pearl wholesalers (primarily located in Japan) because C and D grades are considered “necklace material.” A/B lots are sold loose – for use in earrings, pendants and rings. They are essentially the cream of the crop.

At the September Hong Kong show, Hisano and I purchased several lots from a broker and a producer from Tahiti. Shortly after returning to Los Angeles, another farmer/friend from Tahiti came with a single, large lot of round, circle and drop Tahitian pearls. These lots combined are the pearls we are sorting and turning into strands for the upcoming holiday season. Because we typically only do this twice per year, I’ve decided to document the process here.

To begin with, we start with a lot of loose, undrilled pearl lots.

Thousands of loose pearls from Tahiti in separated lots

The first step in the process is the separation. This process took us nearly a week.

All the pearls must be sorted by their different attributes

Hisano works on sorting out the pearls by color for strands.

Sorting the Tahitians by color

Not all “black Tahitians” are really black. Some are naturally pistachio and others are blue green.

Natrual color pistachio and blue-green Tahitian pearls

My job was examining every single pearl and separating them into surface quality categories. This can be very tedious work because some spots may be smaller than a pin prick. But each spot counts, so each has to be counted.

Examining each individual pearl looking for any surface blemishing

The next step is separating out all the round Tahitian pearls that we’ll need this season for earrings, pendants and rings. We select by color and overtone, and as you can see, the color differences can be quite subtle.

The pearls must finally be drilled and matched onto temporary strings. From here, they will be graded once again, individually photographed one-by-one, and then added to the website over the course of the next two weeks.

Examining the first drilled and matched strands of Tahitians

If we did our jobs right, each strand will have its own unique color combination and character. Very few other pearls cover such an array of dazzling colors.

Circled and drop-shaped Tahitian strands

A few strands of circled and drop-shaped Tahitians with intense colors

Silver-peacock drop strands

Drop strands with lighter body colors and beautiful, subtle overtones

Round Tahitian Strands

Round Tahitian strands showing off the tremendous color range

Colors can be so subtle, every strand needs its own individual photo.

Pearl Paradise Lookbook Fall/Winter 2013

Twice a year I go into hiding (primarily in my office) for about three and a half weeks. I take very minimal custom orders, take very short breaks to eat and go home very late. Excluding the November to December holiday season, it’s the busiest time for me and the creative team. We create Lookbooks; catalogs filled with new jewelry designs for the upcoming season. These lookbooks are aimed for semi0-annual events that our PR team holds in New York. We call it the “Editorial Event” and the team holds numerous appointments with stylists, bloggers and editors from magazines like Martha Stewart Weddings, O, Elle, and so on. Through these appointments our jewelry gets pulled for photo shoots and styling celebrities. We’ve been lucky to have our pearls on Angelina Jolie, First Lady Michelle Obama, Taylor Swift and Olivia Wilde to name a few.

When I go to Hong Kong for our buying trip, or to the Tucson Gem Shows, I am always on the lookout for unique finds that can be featured. We create 4-6 collections for Pearl Paradise for each lookbook. Fall/Winter 2013 we created 5 collections: Grand, Petite, Carved, Gray and Essential Collections.

On one of our Hong Kong trips we bought a loose lot of very large Tahitian baroque pearls and were able to create large strands that were up to 16 mm in size. We paired the pearls with findings that were black rhodium plated to give a dark edgier look – the Grand Collection.


Following the Grand Collection (and for my affinity for tiny pearls) I created the Petite Collection.
This collection was particularly a “win” for us. The Empress necklace was featured in Martha Stewart Wedding magazine recently. This piece was a challenge in all levels. It took me hours to knot and nest the strands and we had to re-shoot many times to lay the piece for photo. Angela spent a lot of time retouching the photo as well but worth all the hard work!

We introduced the Galatea carved pearls in our Carved Collection. We had never bought Galatea pearls before and we wanted to see what the reaction would be. Our PR team loved it, and they are currently working on some press coverage. I personally love the necklace with different carved designs on each pearl with a hidden magnetic clasp.


The Gray Collection is something very different from a standard Pearl Paradise items. We like to have pearls that are in natural colors (except for black Freshwater, black Akoyas and chocolate Tahitians) but when I saw these dyed gray fireballs I wanted to give it a try. I designed it with white gold and diamond link components to mix the organic curvy shape of pearls with geometric lines.


We are constantly getting “pull requests” for classic pearl styles. Through the years of creating these lookbooks, we’ve become sort of the go-to company for pearls. The Essential Collection shows our most popular classic styles and some with a little twist of imagination.

Our best seller Freshadama necklace in 7.5-8 mm


All of these styles are designed, made, photographed and cataloged in a short amount of time along with 10-15 collections that we make for our sister site Pearl Collective. We now have a team of five that work around the clock (while also working on the day-to-day Pearl Paradise operations!) to make this happen. It’s an exhausting project but always an exhilarating one!