Alternatives to Diamonds – Simulants

Want to enjoy the latest trendy diamond-like jewelry without pinching your wallet? Consider diamond simulants!

Diamond simulants are imitations that look like diamonds. They are NOT diamonds. They do not have the same physical or chemical properties of diamonds. As these manufactured ones can be made in quantity, diamond simulants are thus less expensive than diamonds!

Image credit: AOTC

Under magnification, we can make a separation of diamond and its simulants.  Notice that a diamond’s excellent hardness makes it possible for it to achieve very sharp facet junctions and superior polish. In contrast, a simulant’s facet junctions appear more rounded, and it tends to show more signs of wear – abrasions and scratches, and lesser luster.

Note also a diamond has higher thermal conductivity than almost any simulant. This means a diamond stays cooler when exposed to heat. It feels cooler to the touch than a simulant.  Additionally, a diamond has lower Specific Gravity (SG) than most simulants.

Keeping in mind the differentiating properties, and armed with the right tools and equipment on hand, making a separation can be easy.   Without any prior training, a thermal tester makes separation even easier!

Image credit: Jewelry Notes

This instrument provides a quick and reliable reading on mounted or loose stones. Hold the tip of the tester’s probe against a facet. Repeat the test if the tip of the probe touches the metal. Adjust for conditions such as the mounting, the temperature of the room, the identity or size of the stone, as they can sometimes affect the results.

Traditional standard thermal diamond testers CANNOT differentiate a synthetic moissanite (moissanite) from a diamond. A moissanite is a manmade material whose thermal properties are so close to those of a diamond that it can be mistaken for a diamond.  Today, the stones are also put through electrical conductivity test to tell them apart. Between a diamond and a synthetic moissanite, a diamond has lower electrical conductivity. The latest tester models available on the market combine heat/electricity testing for greater accuracy.

Alternatives to Diamonds – Early Simulants

glass

Glass has been an effective diamond imitation since the 1700s. Used in less expensive fashion jewelry, it is also known as “stras” or “strass,” named after a well-known French jeweler Georges Strass. The strass method adds metal powder to faceted glass to give it more glitz like a diamond.

Another name for this type of glass is “paste,” derived from the Italian word “pasta.” This is because early Italian glass makers thought the molten glass looked like boiling pasta when they stirred it. Many Victorian rhinestones are also referred to as paste.

foilbacks

Originally, rhinestones refer to simulants made from colorless quartz from the Rhine River. Today, it is a common term for foilbacked or colorless lead-glass imitation. Foilbacking was a clever technique used in the old days to date to back the stones with foil to add brilliance, enhance or change color.

Image credit: etsy

 

This technique was not restricted to diamonds. Often used on other gemstones, even glass, leading you to believe it was a sapphire or ruby in the setting.

Foilbacks are fairly common in estate jewelry. A perfect example can be found in Doris Duke’s jewelry collection. This is an antique topaz brooch designed as a vari-shaped foiled-back colorless topaz tree mounted in silver c. 19^th century. It was sold for $16,730 at a Christie’s auction.

Image credit: Jeweldujour

In the late 1800s, Daniel Swarovski invented a machine to automate the cutting of glass with facets, resulting in the readily available high quality rhinestone crystals since, and flooding the jewelry market since with affordable jewelry.

doublets

In the mid 1840s, jewelers began to use garnet-and-glass doublets as diamond simulants. This consists of a reddish garnet top thin enough to allow it to take a face-up color from the glass base it is fused to. To make a quick detection, rock the jewel under a light, you should be able to see a difference in luster between the top and glass base.

Alternatively, do the red-ring test. Place the garnet-and-glass doublet face down on a white background. There should be a faint red ring inside the girdle. Similar to foilbacks, these simulants won’t be found in modern jewelry. They are likely to show in antique and estate jewelry.

Antique Victorian 10k Rose Gold Garnet Doublet and Seed Pearl Ring c. 1800s

Image credit: etsy

 New doublets comprise of synthetic spinel or synthetic sapphire crowns and strontium titanate bases. Others deceptively use diamond crowns cemented to bases of other materials.

flame-fushion simulants

Created by French chemist Auguste Verneuil in the late 1800s, flame-fusion is a process of creating synthetic crystals for commercial use. Powdered materials are melted over a flame and cooled until they crystalized. Rubies and sapphires were the first gem materials synthesized with the flame fusion process.

Also called the Verneuil process, it was modified to produce colorless synthetic spinels. Colorless synthetic sapphires and synthetic spinels were used as diamond simulants since they can be inexpensively produced. In the case of synthetic spinels, they are commonly found in class rings or imitation birthstone jewelry.

Alternatives to Diamonds – Natural Simulants

Natural gemstones, as long as they are colorless, can stand in as diamond simulants. Natural colorless gemstones used as diamond simulants include beryl (goshenite), corundum (white sapphire), quartz, spinel, topaz and zircon. All these gemstones also exist in synthetic synthetic form, and all except for zircon can be easily distinguished from diamond because of its lower Refractive Index (RI) and dispersion.

Take a look at these pictures, can you tell these stones apart?

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Diamond is a single refractive gemstone whereas zircon is a double refractive gemstone. So under magnification, you will see double images of the opposite facets.  Natural zircon comes in an array of rainbow colors.  Heating made its colorless form more common in the 20^th century to be used as diamond simulant that dominated the market a while. Due to its softness, zircon chips and scratches easily. And because of heating, zircon becomes brittle. For these drawbacks, zircon is rarely used as a simulant these days.

1. Ippolita Silver Rock Candy Ring in Clear Quartz (Image credit: Polyvore)

2. Goshenite Engagement Ring 2.52 carat in 14k White Gold (Image credit: Resa Wilkinson Jewelry)

3. Celyon 3-gems White Sapphire Ring 1.6 carats in 14k White Gold (Image credit: Planetary Gems)

4. Emerald cut White Topaz Ring (Image credit: Polyvore)

5. White Zircon Ring (Image credit: AJG Gems)

6.  White Spinel Class Rings (Image credit: Imagarcade)

Alternative to Diamonds – Modern Simulants

From the second half of the 1900s, there was a parade of diamond simulants in the jewelry market. Some made it successful. Some disappeared as suddenly as they appeared.

Synthetic rutile

Synthetic rutile served briefly as a diamond simulant but it’s no longer produced. It can possibly be found in some estate jewelry. One drawback of synthetic rutile as a diamond simulant is its low hardness – it quickly shows signs of wear.

It’s pretty easy to tell synthetic rutile and diamond apart because by appearance, synthetic rutile has a very artificial look with lots of colored fire.   Synthetic rutile has one of the highest RI and dispersion than any material, way above that of diamond. Even with unaided eyes, its rainbow colors are so obvious it can detract from its already good brilliance. Besides, synthetic rutile has a yellowish body color that is not easily disguised. Under magnification, synthetic rutile will show double images of its opposite facets as it is a doubly refractive stone, whilst diamond is singly refractive.

Image credit: JTV

Strontium Titanate

Strontium Titanate was developed in the 1950s as a simulant. It was fairly attractive because it is colorless and singly refractive like diamond. However, due to its low hardness, it was too soft and brittle to be used in jewelry, especially rings.

6mm 1.29 carat Candlelight Strontium Titanate

Image credit: JTV

Apart from being a simulant, strontium titanate has also been used as a base for assembled stone fused with a sapphire or spinel crown. These days, strontium titanate is still produced for industrial uses, but its use as a diamond simulant has declined greatly.

Interestingly, long after its heyday as a diamond simulant, the natural form of strontium titanate, mineral tausonite, was found in 1982.