"She had in her hand a beautiful gold chain.  There was a locket attached and the rhinestone in it sparkled like a diamond in the morning sun." - Marjorie Milton, "A Lonely Soul", McClure's Magazine, Volume 4,  May 1895.

For centuries, people have gushed over these tiny bits of cut glass but what exactly is considered a "rhinestone" in today's fashion landscape?  Like anything that changes over time, one generation's definition is very different from the next.  We know they sparkle and aren't real diamonds but in terms of price, composition and usage, the modern day concept of a rhinestone gets a bit fuzzy.  It's time to give these stones some clarity!

Early in the 18th century, inhabitants of the Rhine River Valley in Germany discovered what could be called the first imitation diamond - rock crystals sitting in the riverbed that shared some of the properties of actual diamonds. These pebbles weren't plentiful enough for mass production and were still relatively expensive as each had to be hand-cut and polished after being extracted from the river bed.  Unlike today's "rhinestones", these stones formed naturally inside the earth, untouched by man until they were gathered from the river, then refined by skilled craftsmen.

These river stones were relatively scarce and too costly for mainstream fashion.  Despite the obvious appeal of fake diamonds, the Rhine River stones didn't have enough bling for the fashion crowd's buck.  In the 1720s, two major advancements pioneered by jeweler Georges Frederich Strauss, would seek to change that.  First was an increase in the stones' brilliance by coating the lower side of the stone in metal powder.¹ Then Strauss replaced the rock crystal itself with manufactured glass "paste" - which lowered the price and greatly increased availability.  The Parisian socialites took notice and the new "rhinestone" was quickly headed to the fashion spotlight.

Rhinestones were further refined in 1892 when Daniel Swarovski patented his revolutionary glass-cutting machine and moved his factory to Austria where the company would establish itself as a major player in worldwide fashion.  An endless variety of shapes, colors and coatings followed.  In 2013, Swarovski reformulated it's crystal content with a new lead-free standard, making it acceptable for children's wear.  The rhinestones of Georges Strauss, both in appearance and composition, had become relics of the past.

Yet understanding the modern usage of the term "rhinestone" and reaching an appropriate definition isn't as easy as it used to be. The catch-all term - "imitation diamond" which fit the popular usage a century ago, is too broad as a modern definition.  Many stones that are now classified as "imitation diamonds" are no longer considered rhinestones and vice versa.  At the end of the 19th century, prior to Swarovski's entry into the marketplace, there was already confusion among experts:

 "...a controversy [...] concerning the true nature of 'Rhinestone', a lexicographer of eminence claiming it to be quartz, whereas it is known to be paste."  - Transactions of the New York Academy of Sciences, Volumes 10-11, 1891

Despite these minor confusions about the content of a rhinestone, classifying them in the 19th century was a breeze:  if it's real, it's a diamond - if it's fake, it's a rhinestone. Today things are a bit more complicated.  Cubic zirconia stones, lab-created synthetics and various crystal cuts, settings and colors are all produced and sold in large quantities.

Basic crystal stud earrings can be purchased for under $20 while a one karat synthetic diamond stud can retail for more than $300.  These huge price discrepancies can be attributed to the stone's cut, clarity and color (the rating systems for diamonds themselves) and well as hardness - how easily it can scratch.  Many high-end lab-made stones have now reached the point where they have all of the properties of real diamonds and are nearly impossible to distinguish from the real thing.  These are established at the high-end of the market for imitation diamonds and not classified as a rhinestone, crystal or CZ.

In today's fashion speak, the term "rhinestone" occupies the lowly space of inexpensive, mass-produced crystal stones - entry level sparkle that's available everywhere.  The $14 drop earrings sold at Claire's and produced by the thousands in a Chinese factory are commonly referred to as rhinestone jewelry. The flawless CZ jewelry so often worn by celebrities on the red carpet is definitely not considered rhinestones - at least not in this century.  High-end stones are rarely used for clothing embellishment so "rhinestone" still has a little cache in this context, as the term appears in product descriptions for dressy apparel at nearly every price point. 

The quality and type of metal setting also plays a role.  Synthetic diamonds, like real ones, are hand set by a professional jeweler while less costly stones are held in place by machine-made prong settings, dabs of glue or hot-fix.  Today's rhinestone jewelry often has a flat metal backing that does not permit light to shine through the stone (which is foil coated anyway) - light can only be reflected from the front.  CZ jewelry uses a more refined setting where the stones can be viewed from both the front and back (like fine jewelry).  This is particularly noticeable on dangle earrings where the reverse side is sometimes visible.

How about shape?  Rhinestones generally come in two shapes - chatons (pointed back) and flat backs.  Chatons are commonly used in jewelry, handbags, appliques and anywhere else where the metal casing can be accommodated.  Flat backs are most often found on clothing and shoes and applied directly to the fabric without a metal casing.   Both shapes usually have foil (metal powder in Strauss' day) applied to the back.² Of course, most real diamonds and CZs are also cut with pointed backs - known as a "pavillion", to optimize the stone's fire and brilliance but better stones are never foil coated.

Can a stone's chemical composition alone define it as a rhinestone?  Not easily, as companies like Swarovski are highly secretive about the manufacturing process and chemical makeup of their crystal - sort of like Coca Cola's secret formula.  Crystals and CZs are made from different processes involving numerous raw materials but with today's technology, both are so precisely cut and colored that the average consumer could never tell them apart.  Besides, we're looking for an everyday definition, not a technical one. 

Our modern day definition should take into account how the term is used in shopping and fashion design - the "common usage", if you will.  So it is a rhinestone or not?  Based on what we've learned, a rhinestone in 2015, must be all of the following:

1)  A manufactured stone with a flat or pointed back

2)  Incorporated into apparel and accessory design with metal settings, glue or hot-fix

3)  Priced lower than other imitation stones such as cubic zirconia or synthetic diamonds

Let's take this three-part definition for a test drive and see what happens:

Giavan bridal sash: Rhinestones, no doubt.

Giavan beaded crystal bracelet:  Drilled beads aren't rhinestones.  How about the clasp?  Definitely.

Giavan vintage style crystal brooch:  You bet.

Giavan pear-shape drop earrings:  Prong setting similar to fine jewelry with stones visible from behind - not rhinestones.  These are CZs!

Tiffany three-row ring:  Diamonds, not rhinestones.  Source:  Tiffany.com

IPhone case:  Absolutely.

When it comes to glitter, it's safe to say rhinestones aren't leaving us anytime soon.  A hundred years from now, when they're made with light-sensing diodes that lighten or darken according to our mood, I think they'll still be called rhinestones.  So here's another definition that will stand the test of time:  Little sparkly gems that make things pretty - things I can afford!  

¹ Collector's Weekly, "Antique Past Jewelry", http://www.collectorsweekly.com/fine-jewelry/paste

² Rhinestone Guy Guide, "What's What?", http://www.rhinestoneguy.com/allaboutrhinestones.html