GEM GEMSTONE TOOLS / IDENTIFICATION KIT x 4 , Set B

Top-of-the-line set, a good combination of Refractometer with Built-in LED and Index Oil, New Calcite Dichroscope, Small Diffraction Spectroscope and Chelsea Filter. Made carefully with professional craftsmen to insure quality, accuracy, durability, and comfortability. Below are the devices included in the package.

1) GEM REFRACTOMETER with Built-in LED Illumination and Index Oil (GR-701):

The GR-701, commonly known as Gemstone Refractometer, is the primary and most powerful tool in identify and authenticate polished precious and semi-precious gemstones and observing the optical properties and the structure of gemstones. This model is just as good as the expensive models used in gemological institutes. With the aid of Contact liquid (RI Fluid), that will create an optical contact between the glass and the gemstone, you can measure or test the Refractive Index of faceted stones, transparency or opacity, and its beauty, durability and scarcity. The refractive index (RI) of a gemstone provides the single most important piece of information to a gemologist seeking to identify an unknown stone. Due to its chemical composition and crystallization structure, each gem has a typical refractive index. In fact, you can also use this tool to measure R.I. for many minerals in crystal form as long as the crystals have a flat and polished face. Through these parameters, you can determine whether the gem is a Single Refraction (Isotropic) or Double Refraction (Anisotropic or Birefringence).

GR-701 offers you the worry-free, light and easy way to identify and/or authenticate your most precious gemstones.

 

Features:

• Convenient & easy to carry
• With built-in LED illumination that makes it a carry-and-use-it-anywhere device
• Comes with Automatic Temperature Compensation (ATC) that let itself adjust to the climate
• A bottle of Refractive Index Fluid is provided
  
• Approved by strict quality and safety standards
• Undoubtedly durable and very reliable

Specifications:

• Measuring Range: 1.30 ?V 1.81 RI
• Minimum Graduation (RI): 0.01 RI
• Illumination: Internal LED illumination with momentary switch
  
• Size: 35mm x 63mm x 115mm
• Scale Division: 0.01 nD
• Weight: 0.4 kg
• Ranges of Application: Laboratory, Gemology
  
• Filter: Polarizing filter
• Power Source: 1.5V x3 button batteries

Accessories included:

• Small Vial of 1.800 Refractive Index Oil
• Polarizing Filter
• 1.5V x3 button batteries
• Pouch Case
• Refractometer Index Reference List (For 77 common gemstones, i.e. Calcite, Jadeite, Quartz etc.)
• User's Manual

Operating Information:

• Open the upper cover then wash the gem and prism with alcohol.
• Lay the instrument on the worktable. Drop a little bit of special refractive oil onto the surface of prism and press it by a thin glass bar. (Be sure not too much or too little)
• Make the ground surface of gem to be measured is close to the prism, press it again lightly, make refractive oil distributed evenly between the two surface. Then close the upper cover.
• Press the Led momentary switch, make sure that the internal light source is turned on when testing.
• Move the eyepiece up and down and adjust the diopter accordingly. By this time you can see a light/dark boundary in the viewing field. The gradation (shade) on which the boundary located is called the refractive index of gem.

• MEASURING METHODS:
• Remove the polarizer. Turn it onto eyepiece. Then turn the polarizer lightly. You can only read the refractive index value in one direction at a time because the polarizer only allow the light vibrated in one direction to pass through.
• Then turn the polarizer through 90¢FX, you can measure the refractive index value of the light vibrated at right angles to that mentioned above.
• Turn the gem in the same direction through small degree then turn the polarizer lightly according to above method, you can read the two refractive index values of the light vibrated at right angles to each other.
• Operate continuously until the gem is at 180¢FXposition to its initial position. From a number of groups of measured refractive index values you can find the maximum and minimum refractive index. The difference between the two values is the birefringence of gem.
  

Maintenance:

• After measurement, remove any dirt from the refractometer's housing (casing) then clean prism and the gem with alcohol to remove the refractive oil on it.
• Put back the refractometer into the box for protection.
• Remove the Battery from the Battery compartment if you are planning on not using the Refractometer for a long period of time to prevent leaks or molds that can damage your device.

Warranty: 2 years warranty (24 months)

The Product
	Included: Refractometer Index Reference List i.e. Jadeite Refractometer Index : 1.660 - 1.680 Reflective Index on PRM / PDT : 32 - 36

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2) Dichroscope (CLMG-7208):

Dichroscope show whether or not a stone is dichroic (reflects 2 colors). This can be helpful in differentiating stones of the same color from one another. Dichroscopes can be useful with identifying gemstones that are still in the rough and when stones are set and difficult to get to with other instruments. Light entering the dichroscope is broken into two polarized rays that have vibrational directions at right angles to each other. The two images in the dichroscope represent the polarized light and the pleochroic colors signifies doubly refractive stones except if the stone is viewed thru the optic axis. Single color in the dichroscope represents singly refractive stones.

The advantage of the dichroscope is that the two pleochroic colors that may be characteristic of a given direction in a doubly-refractive gem are seen side by side. If no dichroism is identified in the first assessment, the stone can be turned and viewed in other directions. Trichroic gems can also be distinguish and will reveal three colors if the stone is viewed in three directions perpendicular to each other.

Specifications:

• Type: calcite
• Diameter: 15mm
• Length: 60mm
• Body: Metal

Accessories included:

• Leather Soft Case
• User Manual
  

Warranty: 2 years warranty (24 months)

The Product

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3) Small Spectroscope (CLMG-7206):

A handheld spectroscope for visible light shows the absorption lines of the elements involved in producing its color. For instance, it helps to separate ruby (chrome) against red or pink sapphire (iron). Spectroscope breaks up the light that is being transmitted from a gemstone to its spectral colors. The process allows the gemologist to see the various wavelengths absorbed by the gemstone. Thereby allowing the gemologist to know what elements are contained in the gemstone that are causing the absorption. Making this as one of the most important tools in identifying gemstones.

Spectroscopes allows you to analyze a loose or mounted stone's spectrum. They help distinguish naturally colored diamonds from those that have been irradiated and help to distinguish natural stones from synthetics by the stone's selective absorption of certain wavelengths.

Specifications:

• Length : 50mm
• Diameter : 14mm
• Material : Brass (Durable)

Accessory included:

Leather Carry Pouch

Warranty: 2 years warranty (24 months)

The Product

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4) Chelsea Filter (CLMG-7300):

An essential device in identifying colored stones. While it was originally intended to rapidly differentiate between genuine Emeralds and the pastes and doublets which resemble them, it also is a valuable aid in identifying other colored stones, as well. Designed to transmit only deep red and yellow-green light, and the best results are obtained when stones are examined under a strong electric light. Just hold the filter close to the eye with the stone or stones (for a number of stones can be examined at one time) receiving as much light as possible. Under these conditions, Emeralds (absorbing in the yellow green) usually appear distinctly red or pinkish in color, the actual tint varying from merely pinkish in the case of pale stones, to a rich almost ruby red for better colored specimens. On the other hand, most imitations of the genuine stone (pastes, doublets, soude Emeralds) retain a green appearance. A helpful tool in identifying certain red, blue and green stones.

In rare cases certain emeralds, most notably from South Africa, may not show any pinkish color at all. A synthetic emerald will react the same as a genuine one. Rubies (both genuine and synthetic) appear brilliant red under the filter. Synthetic blue spinel appear yellow-orange or pink while aquamarine and sapphires appear green or green-grey.

This Chelsea color filter has a glass filter which gives better clarity, reduces distortion and provide better protection from humidity. With Chelsea filters you can differentiate the genuine emeralds from the fake once, as well as checking the authenticity of aquamarine and sapphires with comfort and ease.

Specifications:

• Filter Diameter: 20mm
• Body: Made of metal

Accessory included:

Leather Carry Pouch

Warranty: 2 years warranty (24 months)

The Product

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