With spinel's ruby-like appearance deceiving some of the brightest minds of yesteryear, it naturally presents itself as the substitute of choice for ruby. An equivalent looking spinel offers all the beauty, rich color, rarity, history and glittering adamantine luster of ruby, at a fraction of the cost. In fact, the only thing really holding back spinel's recognition is the fact that is rarer than ruby - too rare to make it into the modern jewelry market in any substantial volume.

While usually noted for its crimson red hues, spinel color hues are actually far more diverse than just red.

Spinels of all colors have been found in various different locations worldwide. The market of today sees reds, pinks, oranges and pale blues, and a few other "fancy colors."

While color preferences are always subjective, the ideal spinel colors display intensity and richness without appearing overcast by black or brown overtones.

Colored by metallic trace elements, spinel can be found in the following colors, which are listed in descending order of value:

Cobalt Blue Spinel

Sri Lanka sometimes produces blue spinels that are colored by cobalt. Such "cobalt blue" spinels are highly prized by collectors, with the most intense and vibrant colors possessing an almost unique blue. The value of these intense cobalt blue spinels can sometimes exceed the finest red spinels.


Red Spinel

With the ideal red spinel color being identical to fine Mogok ruby, specimens should display the intensity and richness of bright crimson without appearing too light or dark. Their ruby-like appearance is buoyed up by spinel's high sparkling luster.

 

Orange Spinel

Orange spinel, which is sometimes referred to as "flame" spinel, can be extremely attractive when richly saturated in color. Their value sits somewhere between pink and red spinel and can at times make very good value and convincing alternatives to padparadsha sapphires.

 

Pink Spinel

The boundaries of pink and red color can be somewhat difficult to define (click here to read about it in ruby and pink sapphire). However, for those spinels that are perceived to be safely within the "pink" color zone, bright, highly clean, attractive specimens can be obtained for very good value.
 

Fancy Spinel

Starting from the most valuable of the fancy spinels, this category encompasses violet, purple, blue-green and green. This spinel category displays all the breadth and depth of fancy sapphire, while offering comparable beauty at value prices.

The Carat Weight Of Spinel Greatly Affects Per Carat Prices

Large size, clean spinels are generally not considered rare, but their frequency is far less than tourmaline or quartz based gems. However, as red and blue spinel colors move closely inline with the colors of top quality Mogok ruby and top quality blue sapphire, specimens occur mainly in smaller sizes. This convergence of smaller sizes with top quality colors, renders 7 Carat+ top color quality specimens to be regarded as rare and highly valuable.

As per usual, as the carat weight of a gem increases, so does its per-carat-price. Large spinels are rarer than smaller spinels, meaning carat prices increase rapidly as carat weights increase. Like virtually all other gems, spinel pricing suffers from a "non-linear-scale of increments", and this is especially seen in larger sized specimens of better qualities.


Freedom From Inclusions

Ideally a spinel should allow the free transmission of light throughout its body without any hindrance - quite literally, the ideal is "crystal clear". However, as with all gems, reality tempers our expectations with a few of nature's fingerprints.

The GIA divides all colored gems into three categories for the purposes of clarity grading, based upon their habitual tendencies to exhibit inclusions:


TYPE I Often virtually inclusion-free

TYPE II Usually slightly included
TYPE III Almost always included


Spinel is categorized as a Type II colored gem, meaning specimens are frequently slightly included and fall just short of being thought of as a habitually flawless gem type. While ruby and red spinel may share the same broad, generalist Type II category, experience teaches us that in reality red spinel is habitually cleaner.


Shape & Cut

Due to the octahedral nature of spinel rough, cushion cuts are frequently seen, taking advantage of the squarish cross-section shape of rough spinel crystals to save on valuable carat weight. Trilliants are crafted out of "macles", which are triangular twinned octahedral crystals. All other types of cuts are seen too, from oval to rounds, as well as other shapes such as emerald cuts, pears and trilliants.

Perfect octahedral crystals are sometimes set into jewelry in their original uncut octahedral states. The Burmese refer to these gems as "nat thwe", meaning "spirit polished." Sometimes "nat thwe" spinels will receive a very light polishing.

 

Classical Sources Of Spinel

Now that the mines of Badakhshan have been resigned to ancient history in terms of market supply, the Mogok Stone Tract in Upper Burma is universally recognized to be the premier producer of red, pink and orange spinel. Sri Lanka also produces small quantities of fine quality spinels, mostly in the blue and violet colors. Tanzania and Madagascar also produce spinels of all colors, while black spinel is recovered alongside blue and midnight blue sapphire in Kanchanaburi, Thailand. However, similar to ruby and sapphire, out of all of these sources, only two locations matter when it comes to kudos - Mogok for red spinel, Ceylon for cobalt blue.

Treatment

Spinel is generally not enhanced.