Emerald Hydrothermal method
Crystals grown by Hydrothermal method belong to a group of high-quality, expensive lab-man-unfractured stones, which are also called recreated or cultivated stones (created or cultured gemstones).
Emeralds have been always among the most expensive colored minerals, a segment that includes rubies, sapphires and alexandrite. The price of an emerald can be as high as 25 000 USD per carat. Some transparent dark emeralds can be more expensive than diamond cuts of the same weight which are sold worldwide. The huge popularity and high cost of emeralds has led to an increase in sales of different substitutes such as glass, cubic zirconia, corundum etc. Such "imitations" can be easily identified by experts as well as many customers due to their marked differences from the natural stones.
The market's need for high-quality analogues of emeralds has resulted in elaboration of the materials, which possess all the physical, chemical and optic properties of the natural stone. Such crystals are internationally referred to as created gems.
Experienced specialists from RusGems recrystallize low-quality natural emeralds which undergo a multiple-stage technological process to create an ideal gem. A created emerald of RusGems is a gem, which is revamped and brought to perfection by means of using the hydrothermal method of growth (common abbreviation is НТЕ).
The main advantages of HTE are as follows:
- Excellent quality with reasonable price. HTE has the same properties as a natural emerald, but its price is a thousand times less than that of the natural analogue
- Most emeralds in today’s market undergo primitive refinements such as polymer or oil impregnation to improve marketing appearance. Such improvements do not last long and gem flaws will show up sooner or later. Recrystallized emeralds do not require intensive care and won't change in appearance even over a long period of time
- Full control over the creation process enables variations in crystal gradations depending on the client's preferences: colors may vary from bright Colombian up to dark Uralian or Indian ones. This is achieved by changing the proportion of natural colorants used in the process
- The structure of a recrystallized emerald is very much identical to the organic stone so therefore it can contain inclusions and flaws, which are typical for organic minerals. Such a structure is achieved by control over the growth stages. Thus, it is not possible to employ standard methods to identify a recreated stone, which would be based on simple assessment done in terms of its spectrum, refractive index or presence of inclusions. To get an expert opinion, it is recommended to only contact certified gemological laboratories
Production of HTE emeralds at the factory of RusGems totals 50 kg per month. We are ready to offer customers three varieties of recrystallized emeralds such as Standard, Colombian and Biron emeralds.
Specific features of synthetic crystal of Colombian Emeralds are:
- Bright color. Green stone with intensive blue tone of medium or low saturation. This stone has the color identical to the one of the Colombian analogue
- A set of impurities, which defines the structure and imperfections, is identical to the one of a natural Colombian emerald. Natural emeralds as well as HTE emeralds contain vanadium and chromium impurities
- Absolute correspondence between diagnostic properties of the HTE emeralds and natural Colombian emeralds. This means that it is extremely difficult to identify recrystallized material. For example, a well-known testing approach, which employs the Chelsea filter, helps to identify the emerald crystals of RusGems as the ones that are identical to natural Colombian emeralds
- Thus, it is impossible to distinguish the artificially created stone from the natural prototype based only on its color and visible flaws
Main diagnostic features of HTE and natural emeralds are identical, so we recommend you to contact only certified gemological laboratories to get their expert opinion on this matter.
RusGems offers one other variety of created emerald. Biron emeralds as well as other emeralds, which are created from natural stones, represent the best analogues of natural emeralds. Their physical properties and chemistry completely correspond to those of natural prototypes while their color is identical to natural Colombian emeralds. The only difference of these emeralds from Colombian emeralds is the testing approach which employs the Chelsea filter. RusGems offers different shades: Dark, Medium and Light.
Hydrothermal Emerald of standard (dark) color
Hydrothermal emeralds of a standard color are one of RusGems' basic materials. This material is well known and has established a very strong and extensive niche in the jewelry market as an excellent alternative to natural emeralds thanks to its rich color and purity. Thanks to their physical and optical properties, HTE emeralds are similar to natural stones, but have a low cost.
The table below provides a comparison of the properties of HTE to natural emeralds:
|Properties||Emerald Colombian by RusGems||Emerald Biron and Standard by RusGems||Natural Emerald|
|Chelsea filter||Green||Bright red||Typically green, but sometimes dark red/pink|
|Inclusions||Cracks, fogs and treatment holes, small gas bubbles, which occurred during crystal formation||Cracks, fogs and treatment holes, small gas bubbles, which occurred during crystal formation||Fogs, cracks, holes, double-phase inclusions, calcite, pyrite|
|Size of crystals||Length of 60-100 mm, Width of 3-10 mm||Length of 60-100 mm, Width of 3-10 mm||Typically Length of 2-20 mm, Width of 2-5 mm|
Based on the reasons listed above, we can say that recrystallized stones by RusGems not only complement the jewelry market but also occupy a specialised niche giving rise to a brand-new category of synthetic materials. Now a customer can buy a stone which is completely identical to a natural emerald at a reasonable price.