Frequently asked questions regarding Lotus Gemology's gem testing, gem origin determination and gemstone treatment identification reports.
Frequently Asked Questions about Lotus Lab Reports
How much does a Lotus Gemology report cost?
Our standard softcover report costs ฿4,000 (~ US $115) per stone.
Testing is done on a per-stone basis. We don’t charge extra for weight or origin determination (when applicable). Our philosophy is to charge based on the amount of work that we do to test each stone. It takes us the same amount of work to test a 5 ct as a 10 ct, so we don’t charge extra for the difference.
To view our complete price list, see here.
Do you offer any discounts?
Yes, pre-paid membership discounts are available for volume clients. Starting from ฿100,000 (~ US$3,000) clients get a 10% discount on standard report fees, and discounts go up to 30% depending on the amount pre-paid. Consult our full price list for details.
What is your turnaround time?
Our standard turnaround time usually runs 3–5 business days after the day of submission, but can fluctuate with our workload. When a stone is submitted, we’ll provide an exact due date. Contact our staff for the most up-to-date schedule.
If you need a faster turnaround, we offer express service for an additional ฿4,000/stone (2 business days turnaround) and super express service for an additional ฿8,000/stone (next business day turnaround).
How can I submit a stone in person?
Stones can be submitted in person at our head office in Bangkok or via mail.
Bangkok • Head office and laboratory
Silom 19 Building, 4th Floor, Suite 411
45/1 Soi 19, Silom Road
Silom, Bangrak
Bangkok 10500 • Thailand
Phone: +66 (0)2 117 3616 • Line/WhatsApp/WeChat: +66 (0)99 229 8646
Email:
Hours: Monday–Friday, 9:00–18:00
How can I submit a stone by mail?
Yes, you can ship stones into the lab for reports using your preferred shipping agent.
The most cost effective method of shipment depends on the value of the goods and can vary by location. The following are general guidelines. For exact shipping rates, contact your preferred shipping agent.
Ship with UPS or FedEx
For items of moderate value (~US$10,000) many of our clients have found UPS, FedEx, or their local post services to be the most cost effective.
Please note that goods shipped in this way will be subject to 7% VAT on the declared value of the items.
Ship with Ferrari, Malca Amit, or Brinks
For higher value parcels (~US$10,000+), it is often more cost effective to ship with a specialty shipping company such as Ferrari, Malca Amit, or Brinks.
They have services that can bring the goods in for testing only and avoid paying the usual 7% VAT, as long as the items are shipped back out again. Because of their relatively higher service fees, this option is usually more cost effective for more valuable parcels.
How do I prepare a shipment?
Please email us at
What about return shipping?
We can ship them back to the original sender or to a third party (such as an auction house) as you prefer.
Can you test stones that are mounted in jewelry?
We recommend that stones be submitted loose to facilitate the greatest accuracy in testing and measurements. This is particularly important when you are planning to mount the stones in jewelry.
However, in most cases we are able to accommodate stones that are mounted in jewelry. We will make our best attempt at testing any mounted stones without having to unmount them. If in our testing we find that we are unable to accurately test the stone in the mounting, we will contact you.
What’s the difference between a Duplicate Report and a Re-ID?
Duplicate Report • A copy of a previously issued report. It is the same as the original report, with the addition of a note that it is a duplicate. Limit one duplicate per report.
Re-ID • Get a new report on a stone that Lotus has previously tested. This can be done whether or not a stone has been re-cut. Complete testing will be done, and a new report will be issued with a new date and new report number. If a stone is submitted for Re-ID within one year of the original report, a 50% discount will be applied.
What’s the best way to highlight my most special stones?
We offer a premium hardcover report starting at ฿12,000 (~ US$370) per stone, with additional customizable options, including extra photos, available. Our hardcover reports are crafted with the end user in mind and provide additional information to help them appreciate the rarity and beauty of precious gems.
See our full price list here.
What’s the difference between gold, silver, and black reports?
Gold reports are issued for gems that show no indication of treatment of any type. They show no signs of heat treatment, oiling, irradiation, glass filling, dye, or other treatments.
Silver reports are issued for natural gems that show evidence of enhancements. Stones enhanced with heat treatment (H), heat with fissure healing (H-FH, or “flux” or “borax” heat), fillers like oil or resin (FF-O)
Black reports are issued for synthetic and/or heavily treated gems. This includes lead glass-type hybrid (LGH) stones and assembled stones.

How can I verify whether my Lotus Gemology report is genuine?
The best way to verify a Lotus report is with online report look-up. There you can verify the details of the report as well as download a pdf version by using your report number and PIN.
Not sure how to find your report number and PIN?
For reports dated after February 2015, use this guide.
For reports dated before February 2015, contact
If you have any doubts or questions about a report, don't hesitate to contact us directly.
Will Lotus issue an origin report on my stone?
We issue origin reports when testing reveals sufficient gemological evidence to make an origin determination. Origins are issued at no additional cost to the client.
Can you guarantee that my stone will get an origin at time of submission?
We cannot guarantee an origin report; the final result depends on our testing. If the gemological evidence is sufficient, we will issue an origin at no extra charge to the client.
What types of stones are most likely to get an origin report?
Ruby & sapphire are the most likely to get an origin. We also frequently issue origins on spinel and emerald.
If I don’t get an origin, do I get a discount?
Because we don’t charge for origin determination, there are no discounts for reports that don’t include an origin.
What does it mean when a sapphire’s origin reads Basalt Related or Metamorphic?
In some cases it may not be possible to provide an exact origin determination on a stone. We can often eliminate some possibilities, even if we cannot provide an exact country of origin. In these cases, we will provide as much information as we can.
Sapphires from basalt related sources tend to grow in iron-rich environments at higher temperatures. Basalt related sapphires commonly seen in the market often come from Australia, Ethiopia, Laos, northern Madagascar, Nigeria, Rwanda, and Thailand.
Sapphires from metamorphic sources tend to grow in more iron-poor environments at relatively lower temperatures than basalt related sapphire. Metamorphic sapphires commonly seen in the market often come from Burma (Myanmar), Kashmir (India), southern Madagascar, and Sri Lanka.
Can you distinguish if my Burmese ruby is from Mogok or Mong Hsu?
In most cases, yes. Both will have an origin stated as Myanmar (Burma). Additionally:
A ruby from Mong Hsu will usually have the comment:
In the early 1990s, rubies of extraordinary quality were unearthed at Mong Hsu, in Myanmar’s Shan State. Stoplight red in color, they rank among the finest rubies ever found.
A ruby from anywhere else in Burma, including Mogok, will usually have the comment:
Since ancient times Myanmar has produced gems of extraordinary quality. Alongside other regions, the famed Mogok Valley has earned particular renown for yielding some of the world's most exquisite rubies, sapphires, and spinels.
We do not make a distinction between stones from Mogok, Namya, Mansin, etc.
Will Lotus issue a color type on my stone?
We issue a variety of color types on ruby & sapphire including Pigeon’s Blood, Royal Blue, Cornflower Blue, Padparadscha, and more. We also issue a Cobalt Blue color type for spinel and Imperial Green for fei cui jade.
Is there any way to check a stone’s color type before doing a full report?
Yes. Ask for a Verbal Color Analysis upon submission.
What is a Verbal Color Analysis?
Ask for a Verbal Color Analysis* at submission and we’ll tell you how we would describe the color on the report. This could include what color type it would get on the report (Pigeon’s Blood, Royal Blue, etc), and/ or what hue, tone, and saturation will appear on the report.
We will contact you with the result by the next business day. If you choose to do a full report on the stone, the color check is complimentary. If you would like to withdraw the stone without doing the full report, we’ll charge ฿321 (~ US$10) for the color check.
Things we can check for:
- Will the report say Pigeon’s Blood, Padparadscha, Royal Blue, etc?
- Will my stone get a vivid saturation?
- Is my stone a color change?
- Is my spinel Cobalt Blue?
- Will my stone be “purplish red” or just “red?”
- Will you mention the term “Paraíba” on my report?
*Important Limitations of Verbal Color Analysis
The verbal color analysis is a strictly verbal, non-binding visual check of a stone’s color. The final color call on a report is still contingent on further gemological testing.
Are any stones disqualified from getting a color type?
Yes. If our testing reveals certain features in a stone, it will be disqualified from getting a color type even if we did a Verbal Color Analysis on it. These can include, but are not limited to finding that a stone:
- Is synthetic
- Has a different identity than that declared (for example, if a red stone is submitted as a ruby but testing determines it is a spinel)
- Is glass filled
- Has natural staining and/or artificial filler in the fissures that modifies the appearance of the stone
- Has an unstable color
- Is coated
- Is diffused
Can a beryllium (Be) diffused stone get a padparadscha color type?
No; we do not issue color types for diffused stones because the cause of color comes from external coloring agents.
What does the enhancement code H-FH mean?
H-FH stands for heat with fissure healing. This is commonly referred to in the trade as heat with flux or borax.
Learn more about our enhancement disclosure here.
What will happen if fillers are detected in a stone?
Fillers in emerald
Emeralds treated with colorless fillers will be disclosed as FF-O (fissure filling with colorless oil/resin) with a rating of 1/2/3 (minor/moderate/significant) on the report, and will be issued a silver report.
Fillers in other stones
Stones other than emerald treated with colorless fillers will be disclosed as FF-O (fissure filling with colorless oil/resin) with a rating of 1/2/3 (minor/moderate/significant) on the report, and will be issued a silver report.
If the stone has any other detectable treatment, it will be issued a silver report and reported as submitted.
If no other detectable treatment is found, one opportunity may be provided to remove the filler prior to report issuance. If subsequent testing confirms that the filler has been successfully removed, a gold report will be issued. If filler is still detected after cleaning, a silver report disclosing the filler will be issued.
How does a stone qualify for a "color change" comment on a report?
We use two different calibrated light sources to check for color change, one a D-65 daylight source and one an incandescent source. At Lotus our standard is that a stone must shift at least two adjacent hue positions in order to qualify for a color change.
For example, in the blue range, the hue positions are:
- Blue
- Violetish Blue
- Bluish Violet
- Violet
If a stone is violetish blue in daylight, it would need to move to full violet in order to qualify.
If you would like to know whether your stone would qualify for a color change comment on the report, you can submit it for a Verbal Color Analysis.
What stones can I get a hardcover report for?
I've heard that some sapphires may have an unstable color. Does Lotus check for this?
Yes. Certain sapphires may have an unstable color that can lighten or deepen with prolonged exposure to light. This particularly occurs in sapphires with a yellow-to-orange color component, including padparadschas. The effect is generally not visible in rubies of strong color because the ruby body color masks it. Unstable color can occur either naturally or as a result of artificial irradiation. Exposure to strong light can “fade” or lighten the stones back to what is considered the “stable” color. Exposure to heat can bleach the stable color, but placing the gem in direct sunlight for a period of time (minutes to hours) returns the color to the stable state.
In cases where there is concern that a sapphire may have an unstable color, our gemologists regularly conduct fade tests, exposing the stone to light (without heat) for a prolonged period. The color after the fade test is conducted is the color that will appear in the description and the photograph in our report.
For reports issued after 15 November 2025, the report will also contain a note stating the result of the stability test. Fade tests were conducted prior to that date, although this was not specifically indicated on the report.
Please note that not all yellow to orange sapphires display this color instability.
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