Rare Gem Collection

Every potential Padparadscha Sapphire should undergo Color Stability Testing to check its color. In plain English, certain sapphires can lose their color after exposure to heat or strong light. This phenomenon is relatively new for Padparadscha Sapphires.

Gem Lab Definition

According to many gem labs, the Padparadscha is defined as “a variety of corundum from any geographical origin whose colour is a subtle mixture of pinkish orange to orangey pink with pastel tones and low to medium saturations when viewed in standard light. (LMHC Information Sheet #4, 2018).
The following labs that follow this definition of are:
CGL Laboratory (Japan),
CISGEM Laboratory (Italy),
DSEF Laboratory (Germany),
GIA Laboratory (USA),
GIT-Gem Testing Laboratory (Thailand),
Gubelin Gem Lab Ltd (Switzerland), and
Swiss Gemmological Institute-SSEF (Switzerland).
GIA describes Padparadscha Sapphire: as “salmon or sunset” color. Others compare the color to the flesh of a ripe guava.
In spite of these differing color descriptions, people in the industry usually agree that padparadscha sapphire colors are intensely saturated and range from light to medium pinkish orange to orange-pink. (Gemological Institute of America, 2004).
See some of our lab certified Padparadscha Sapphires.
Alexandrite Gemstone

Where Does The Name “Padparadscha” Come From?

Alexandrite Gemstone

Lotus Flower Picture
Courtesy of GIA

GIA Pioneer Robert Crowningshield, cited one of the earliest recorded definitions of Padparadscha Sapphire: “padmaraga in Sanscrit refers to lotus color or rose red…in Bengali: padmaraga and padmaragmani, ‘mani’ being the suffix for the stone.” (Crowningshield, 1983).

He goes on to conclude that Padparadscha is a semantic change derived from a true Sinhalese word: “padmaragaya (lotus-color). (Crowningshield, 1983). [Picture Left: A Lotus Flower from Crowningshield’s often cited article. Photo Credit: Miguel Rodriguez].

Distinguishing a Padparadscha

There can be great difficulty in distinguishing Padparadscha Sapphire from a fancy sapphire.
How do you tell the difference between a Pink Sapphire, an Orange Sapphire, and a Padparadscha Sapphire?
Compare the three stones below:

Pictured Left: GIA Pink Sapphire.

Middle: GIA Padparadscha Sapphire.

Pictured Right: GIA Orange Sapphire.

Genuine Alexandrite

What’s NOT A Padparadscha

Real Alexandrite Stone

A Sapphire Failing the Color Stability Test

The difference between padparadscha sapphire and a fancy sapphire:

While color alone as noted above can show the subtleties between orange and pink and padparadscha, a recent phenomenon has revealed that certain sapphires may appear as padparadscha at first, but fade over time into a pastel pink colored sapphire.

As a result, the LMHC in its Information Sheet #4 Publication updated the list of Padparadscha disqualifications:

1.If the stone has any colour modifier other than pink or orange

2. If the stone has major uneven colour distribution when viewed with the unaided eye and table up +/- 30°

3. The presence of yellow or orange epigenetic material in fissure(s) affecting the overall colour of the stone

4. If the stone has been treated as described in Information Sheets #2 and #3

5. the stone has been treated by irradiation

6. the colour of the stone is not stable and shifting out of the padparadscha colour range (e.g. shifting to pink) by a colour stability test

7. If the stone has been dyed, coated, painted, varnished or sputtered. (emphasis added).


This test, commonly referred to as the “color stability test” exposes the fancy gemstone under high temperature/or strong light over a span of time to determine whether the color remains the same or changes.

An unstable color will become pinkish. Each lab may have a different method of conducting this test.

The important result of any methodology is that a true padparadscha sapphire will not fade under any lighting or heating circumstances.

What’s important to note here is that a sapphire may appear to have beautiful orange pink and/or pink orange hues, but simply fade away and lose it.

The fading must reach a level that falls outside the narrow definition of padparadscha to a point where it simply appears as a pink sapphire.

Why is color stability so important in Padparadscha?

Padparadscha Sapphires are rare. With that rarity comes a premium price. Most gemstone traders understand that the value dramatically changes for fancy sapphires that get a Padparadscha classification on the lab report.
However, not all sapphires deserve the Padparadscha designation. Besides the correct pink orange combination, color stability testing will reveal whether the color is permanent or not. Stones that do not have color permanence do not deserve special Padparadscha designation.

Our Padparadscha Turned Pink

It was March of 2016, when my father and I had just finished walking the annual Bangkok Gem Show when a Sri Lankan Gem dealer invited us to his local office to show us some gemstones.  He presented us with a beautiful clean sweet pinkish orange untreated padparadscha sapphire that we immediately needed to buy. Much to our delight we negotiated the price, and later confirmed the stone as Padparadscha with GIA the following month.

We had many interested buyers for the stone because of its color and size, at over 5.5 carats, such qualities were extremely hard to come by for padparadschas.

Overtime, my father pointed out to me that the stone now appeared lighter than it did in Thailand. Despite his concerns, I dismissed the notion that it was lighter. Many gem dealers have a theory that stones always appear more intense in Asia because of the sun, and lose some intensity upon arrival to the USA.

I eventually realized he was right. The Sapphire now had a pastel color that no longer resembled the perfect Padparadscha.

Alexandrite Stone
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Before labs knew anything, there were rumors about foreign gem dealers leaving their stones out in the sunlight before attending trade shows. This practice would apparently improve color saturation.

Soon as a I began to investigate and piece together what happened to my stone, I had a eureka moment. After multiple trade shows, we noticed the stone stayed under strong showcase lighting, it seemed feasible that this had an effect on color.

We realized we were on to something. Going forward, we decided to do our own testing on our stones. I spoke to some senior gemologists in the trade, who were aware of such a phenomenon in yellow sapphires that called  “trapped color holes.” As far as they knew, this was not something recognized in other fancy colored sapphires. These color centers can also be effected by UV lighting. We bought a UV light and tested it out for ourselves.

Our results revealed that UV lighting turned pastel colors into orange on certain stones. Specifically, our 5.57 cushion actually returned to its original color. We decided that these color shifting stones were going forward, we would leave stones out by our office window to see if they would lose color after one week. This would be our in house test before purchasing any padparadschas.

What lab first identified Color Stability in Padparadscha?

SSEF was the first lab to report this phenomenon in Padparadschas in 2018.

In 2018, the article (which can be found here), discusses how the color stability of sapphires from a certain location would change. They attributed this to a single corundum deposit. However, it would appear that this was not the only mine.

According to SSEF, stones that shift from orange to pure pink will not be called padparadscha. They will be called fancy sapphires with an explanation letter added to the report. 

They key being that Padparadscha must not show pure pink colour shift.

Russian Alexandrite

What other labs perform Color Stability Testing?

In November of 2018, the main international labs followed SSEF.  The Lab Manual Harmonization Committee (LMHC), updated the Padparadscha definition to address color stability test (Information Sheet#4 Read it here).

Members include (in addition to SSEF): CGL Laboratory (Japan), CISGEM  Laboratory (Italy), DSEF Laboratory (Germany), GIA Laboratory (USA), GIT-Gem Testing Laboratory (Thailand) and Gübelin Gem Lab Ltd. (Switzerland).

According to these labs, the term padparadscha sapphire will not apply to sapphires shifting to pink by a colour stability test.

GIA’s Padparadscha Stability Testing

Since GIA has adopted this definition, the color stability test can change results of reports previously classified as Padparadscha. For example, take a look at this 4.10 carat sapphire with 2013 GIA Padparadscha Report that went under new testing.

The seller tried to sell us this stone as Padparadscha. We insisted a condition based on an updated report. The new results were extremely telling:

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Upon return with an updated report, the sapphire was no longer considered a Padparadscha. See below

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If you carefully examine this report, there is a comment that says: “The color of this stone may temporarily change when exposed to ultra-violet light.”

This new report would indicate that the stone’s color has changed so significantly that it no longer meets GIA’s acceptable pink orange or orange pink saturation level.

We were surprised, yet relieved. Our suspicions were confirmed and labs were finally beginning to address this issue.

Even though certain sapphires might fade to pink, it appears to be possible that the color could fade, and still meet the minimal acceptable padparadscha color range. These Padparadscha’s can be considered unique because they change into two varietal colors of Padparadschas consistent with the color’s range requirements.

American Gem Lab’s Color Change Padparadscha

Each Padparadscha Sapphire looks different. The LMHC understand that the hue ranges from light to medium. Pink-Orange, and Orange-Pink combined with light to medium leaves a multiple potential colors.

Color stability testing reveals how saturation can become lighter. The degree of lighter color will either fall outside the range of Padparadscha’s acceptable hue, or still fall within the range.


Real Alexandrite

This 1.12 Cushion is described as Light Orangy Pink and Pinkish Orange. This unique situation shows that certain sapphires with shifting colors can still meet the Padparadscha criteria, granted they do not only appear pink.

The transformation of a sapphire to pink seems to be accepted as a disqualification for Padparadscha.

GRS Color Stability Categories:

GRS has taken a more diverse approach to classifying padparadscha. According to GRS, fancy sapphires have 4 types of color stability.

Type 1: Color is stable

Comment on report: Color stability test applied. No indication of fading was observed. Post-testing exposure to UV- or sunlight will not increase the color saturation and/or cause a change in hue.

Ideally, Type 1 is the top-level color stability a stone can have. In plain english, this means that your Padparadscha’s color will not change under any circumstance. 

Example of Type 1:


Type 2: Color unstable, submission in charged state

Comment on report: Color stability test applied with indication of orange and/or yellow component fading was observed. Post-testing increase of color saturation and/or change of hue by exposure to UV- or sunlight is possible.

Type 2 means your stone has a brightness to it that will go away. The brightness comes back with prolonged exposure to sunlight or UV light. Once the stone fades, the color you see is what your padparadscha will look like most of the time.

The best way to test your stone out yourself is to leave it by the window for a prolonger period of timing making sure daylight is on the stone. We suggest a minimum of 1 week exposure to see if the stone loses color.

Type 3: Color unstable, submission in uncharged state

Comment on report: Color stability test applied. No indication of fading was observed. Post-testing increase of color saturation and/or change of hue by exposure to UV- or sunlight is possible.

Type 3 is the flip side of type 2. If the color already appears faded, and it is submitted to the lab, this is considered “uncharged.” The Charging occurs when sunlight enhances the brightness. 



It seems that depending on the padparadscha charged or uncharged state, you will likely get Type 2 or Type 3 Padparadscha.

Type 4: Color unstable, submission in charged state, stone cannot be re-activated after fading

Type 4 is on the border of being Padparadscha. If the color fades, the permanent seen color might be too light to be considered Padparadscha. In these scenarios, the color of the stone upon submission will no longer look the same when returned to you, and will not be able to return back to the color you originally had.

One of our earliest purchases involved a padparadscha that over time gradually lost its color. This image to the right depicts a 5 carat Padparadscha we bought in 2016.

Over time, we noticed the color faded.

We paid more for the original color which was not permanent.

Alexandrite Gemstone

Padparadscha Buying Considerations

 Each lab report has different standards for gemstones identification. You must consider which lab you want to rely on. Gemstone sellers must disclose any treatments. However, sometimes they might not even be aware of the modern definition of Padparadscha.

We always use independent reputable labs for our gemstones. Our padparadscha are depicted in their actual color. We do not improve the color artificially. What you see in our inventory is what you get.

Never rely on selfserving gem reports issued by the seller to determine whether a sapphire is a padparadscha.

Low to Medium Hue Definition

The definition always hinges on “low to medium” saturation. When a sapphire falls on the cusp of high saturation, it can lose out on the Padparadscha designation. On the color Spectrum, intense pinks and oranges will be deemed fancy sapphires.

Take for example, the image of the 3 sapphires above. GIA described the middle sapphire as Padparadscha but not the other two stones.

This Oval Sapphire below was rejected as “Padparadscha” by GIA, and AGL.

According to GIA, this oval stone is a brownish-orange sapphire.

This is due to the intense (high) saturation.

The subtle difference between medium and high saturation may seem arbitrary, but makes all the difference.

For us, this pear shape padparadscha sapphire on the bottom is the right balance of orange and pink AND the low to medium saturation criteria set out by the LMHC.

Alexandrite Gemstone

A Fancy Brown Orange Sapphire According to GIA

Alexandrite Stone

A Pear Shape Padparadscha Sapphire

The Rare Gem’s opinion that the best and most accurate way a Padparadscha Sapphire can be properly given the true classification is by a reputable gem lab that abides by the standard’s set forth by the LMHC.

We also believe the strict standard set by AGL is sufficient.

We respect GRS is one of the premier gem labs. However, not all GRS lab reports with Padparadscha are the most accurate representations of acceptable color.

Final Word

The only true padparadscha will be one that is supported by a reputable lab. At the end of the day the most important standard to go by is the one accepted by the person who will own the gemstone.See Some of our limited Padparadscha Sapphires