How to test Rubies: An Overview

Rubies are one of the rare and precious forms of gemstones, distinguished from the likes of emeralds and diamonds with its garish scarlet red colour. Meanwhile, market boasts of variety of ruby gemstone beads with primary hues ranging from yellow to blue to even purples! But nothing like the pale rose pink rubies that have ruled the hearts of Dukes and Emperors for centuries.

How to tell if the ruby is real or fake? Here is what gem experts do to distinctly identify real rubies from the cheap imposters.

Primary Identification using Colour Consistency test:

What you see is what you get. Ruby is a blood red gemstone belonging to the family of corundum. The colour is present due to the chromium ions that inundate the crystal lattice largely containing aluminium oxide. If the colour is consistent with fine rutile impregnated in the crystal, it means the ruby is fine and untreated. If you miss out on the rutile, it means that the stone has been treated in heat to look finer and give a more consistent colour. A shade of imperfection is what makes rubies so attractive.

Test to find specific gravity:

Purest ruby corundum will bear a specific gravity of 3.98 with tolerance of 0.5% depending on the source of the stone. A special solution called “Clerici” is used to check the specific gravity of a ruby gem. Since the specific gravity of the dense fluid is 4.0, the rubies are supposed to float and displace the same weight of the fluid.

Note: In market, rubies are available in the range between 3.95 and 4.05 specific gravity.

Test for Refractive Index:

In terms of opacity, rubies can show transparency as well as translucency. The refractive index of a pure ruby is anywhere between 1.763 and 1.768 with dispersion measured under spectrometer coming at 0.018. Cheaper version of rubies and other gemstones have a much lower refractive index, often counted between 1.66 and 1.70.

Double Refraction Test:

Now we are taking serious science. Ruby gemstones do not boast of any particular line of cleavage. The fractures occur in conchoids or splintery manner. The hexagonal crystal structure of ruby and the internal fracture plane splits a single beam of light into two, leading to a phenomenon called Double Refraction. When observed under a polariscope, ruby exhibit birefringence or dispersion of 0.08.

Fluorescence Test:

Rubies are exposed to florescent light and the refraction is checked with Chelsea Colour filter. Luminescence of rubies when florescent light is passed through them bears crimson or orange light. No other stone apart from ruby will give a red when exposed to florescent light. This is a key separation test between rubies and garnets.

Popularity of synthetic rubies:

Use of synthetic rubies is not a taboo! They are imitation stones made by burning scarlet wool under the base. They were largely used to manufacture Ruby Lasers in the 60s. Red spinel gemstones, red tourmaline, Rubellite and Balas ruby are some of the names you should stay away as a buyer.

A look at Top 5 Most Expensive Gemstones in the World

Since the ancient times, gems and jewels act as a symbol of wealth and prosperity. There are numerous gemstones available in the world. They are classified on the basis of various factors, and this in turn plays a great role in determining their price. Some stones emit sparkle and a different hue altogether. Consequently, they have turned out to be the rarest and also the most expensive ones on the earth. They are expensive not only due to their rarity or color, but also because of their characteristics and powers.

A List of The Most Expensive Gemstones:

Below is a list of some of the most expensive gemstones available in the world.

1.  Blue garnet:

When it comes to garnet, you possibly think of a deep red stone. Apart from that, the stone is also available in blue, but they are very rare. The blue hues are generally spotted in the color changing garnets based on the angle you hold them. Therefore, they are highly valuable. The blue garnet is counted among one of the most expensive gemstone in the world.

2.  Red diamonds:

These stones are very rarely available. If you have a close look at Red Diamond gemstones, you will find that these are actually purplish red and not pure red. These look amazingly gorgeous, and hence it can easily be said that it is one of the most expensive gemstones of all.

3.  Serendibite:

Most people have not heard of this gemstone, but it is very valuable. The color of this stone might vary ranging from gray blue to blue green and pale yellow. Some of these stones are also available in black, and many contain no hues or colors, at all.

4.  Jadeite:

It might be one of the most precious stones in the entire world. It might come either in bright bold green or have an emerald hue in it. Apart from that, it might even come in blue or white color. Some pieces of the stone might even contain lots of hues. If the green is brighter, the price tends to rise. It is a type of jade, but it is not the most common variety of stone. If you find affordable jade in the market, it is possibly nephrite. An expensive jade gemstone will give you an indication that you are looking at a genuine jade stone.

5.  Musgravite:

The name of the stone was derived from the place it was first received. The stone is generally violet in color, but it might often appear in grayish tint. Some of these might be lighter while some might be darker in color. Since the stone is incredible rare in availability, it is highly expensive and valuable.

In fact, you should not be surprised to know that apart from the above mentioned ones, there are many other expensive gemstones like red beryl, taaffeite, bixbite and others. These are priced on the basis of different factors. Moreover, the prices might also go up and down from time to time based on their availability and market value. Therefore, if you are looking forward to purchasing any of these stones, you should buy them from an authentic dealer.