Authenticity Guarantee for Jewellery

Diamond clarity

Clarity is evaluated based on the area of the stone that is visible. Areas of the stone that are covered by the setting will not be part of the evaluation. Clarity for VS2, SI1, SI2, I1, I2, I3 will be verified with a - 1 tolerance.

Clarity grade for Flawless, Internally Flawless, VVS1, VVS2 and VS1 stones will not be confirmed unless a GIA report is present. Stones having a carat weight of less than 0.15ct will not be verified for diamond clarity.

Diamond colour

For colourless diamonds, Jewellery experts will verify the listed colour value and accept a –2 tolerance from the lowest value indicated. For example, if a listing states the colour is G and the expert determines the colour is likely I, the diamond will pass colour verification. Similarly, if the listing states the colour is J-K and is likely L-M, the diamond will pass colour verification.

Please note, D-Z diamonds with a weight below 0.25ct will not be verified for colour.

For fancy-coloured diamonds, experts will only confirm non-trade term hues. For example, if listing states that a diamond is “fancy yellow”, experts will confirm that the hue is yellow, but they will not confirm the saturation level. If the listing states that a diamond is “Canary yellow”, experts will confirm that the hue is yellow, but will disregard the term “Canary”. Please note the colour of the setting may impact the appearance of the diamond (i.e. a diamond set on yellow gold may appear less clear).

Diamond Treatment

If the listing states unstable treatment, clarity and colour will not be verified.

GIA will not verify colour treatments for D-Z diamonds.

Coloured stones colour

If a gemmological or trade term is used in the listing and the colour appears to be close to term definition, it is acceptable. If a non-gemmological term is used in the listing, verification will confirm the term used represents the colour of the actual item.

A gemmological or trade term describes specific colours and qualities of gemstones that are typically assigned to gemstones of superior quality and rarity.

Common trade terms for coloured gemstones include, among others, Pigeon Blood Red, Royal Blue and Padparadscha Sapphire.

Carat weight

Stones weighing 0.40 ct. or more per stone have an acceptable tolerance of -10%. Stones that weigh less than 0.40 ct. have an aggregate tolerance of -25%.

Assembled stones

Assembled stones are stones constructed out of two or more materials and are not eligible for Jewellery Authenticity Guarantee.

Common assembled stone types include:

• Doublet: A doublet consists of two joined segments.
• Triplet: A triplet has three segments, or two segments separated by a layer of coloured cement.

Item size

An expert will verify that the size of the item matches the size listed by the seller (i.e., cm, mm, standard ring sizes, etc.). Necklaces, bracelets and bangles will have a tolerance of +/- 0.64cm / ¼ inch. Rings will have a tolerance of +/- 1 full ring size. For long necklaces, 61cm / 24 inches or longer, a tolerance of up to +/- 1.27cm / ½ inch will be accepted.

Please note, resizing an item may result in metal purity and/or composition variances in the area that was modified for resizing purposes (i.e., metal alloys used to modify size may affect metal purity in sections modified).

Gemstone treatments

Gemstones that are eligible for Authenticity Guarantee are commonly treated. Clarity enhancements can be performed on any stone that has a fracture but is more common in some gemstones than others.

Please note coloured diamond treatments will not be verified.

Below is a list of the most common gemstone treatments that are acceptable for verification. This list does not represent all possible treatments that could apply.

• Ruby: Heating, healing of fractures (residues), clarity enhancement, glass filling, dyeing
• Sapphire: Heating, clarity enhancements, titanium diffusion, beryllium diffusion, dyeing
• Emerald: Clarity enhancement, dyeing
• Tourmaline: Heating, clarity enhancement, irradiation (red or pink)
• Topaz: Heating (pink), irradiation (blue, brown), coating
• Tanzanite: Heating, clarity enhancement
• Peridot: None
• Garnet: Heating (demantoid)
• Aquamarine: Heating
• Cat’s eye chrysoberyl: None
• Alexandrite: Clarity enhancement
• Spinel: Heating
• Morganite: Irradiation

Please note, clarity enhancements can be performed on any stone that has a fracture but is more common in some gemstones than others.

Treatments that cannot be verified

• Heating: Aquamarine, demantoid garnet, topaz (pink), tourmaline (blue to green), tanzanite. Low temperature in ruby and sapphire is sometimes detectable but not under Authenticity Guarantee.
• Irradiation: Cannot be proven in any coloured stone. Some blue topaz is assumed to be treated because of its depth of colour.
• Beryllium diffusion: Can be detected but only with sophisticated chemical analysis.
• Additionally, claims that coloured stones are untreated will not be verified.

Gemstone treatment definitions

• Heating: Heating a stone at temperatures that may vary from 300C to 1800C (depending on the stone) to change the colour or improve clarity.
• Healing of fractures: Causing fractures to grow back together during heat treatment using a flux. This is almost exclusively done to rubies and sapphires and is called ‘residues’ in the gemstone trade because of the whitish flux that is left behind.
• Clarity enhancement (fracture filling): Filling fractures that are open to the surface with substances such as oils, resins or glass to make them less visible. In most cases this is not a permanent treatment.
• Glass filling: Usually refers to rubies filled with lead glass, although it can apply to silica glass. Lead glass filling is mostly used on very low-quality ruby that could not be cut into a stone if it were not held together by the glass.
• Titanium diffusion: Using high temperature heat treatment to cause titanium to enter the surface of a sapphire, creating a blue colour in a surface layer.
• Beryllium diffusion: Using high temperature heat treatment to cause beryllium to enter the surface of a ruby or sapphire to change the colour, depending on the starting material. This treatment can be in a surface layer or extend throughout the stone. It is not common for rubies.
• Irradiation: Exposing a stone to ionizing radiation such as fast electrons or gamma rays to change its colour.
• Coating: Applying a foreign material to the outside of a gemstone to change its colour. This treatment is usually not permanent.
• Dyeing: Filling fractures or openings at the surface of a stone with a foreign coloured material to create an artificial colour.

Undetermined results

In some cases, if it’s not possible to determine whether an item is unstable, lab-created or has been treated using then-current techniques and technology, treatment status of the item is undetermined and will pass this verification step.

Stone count

If an item has numerous stones that weigh less than 0.20 ct., the precise number of stones in the item will not be verified.

Metal gram weight

If listed, the total gram weight of the metal-only items will be verified. Metal weights will not be verified on finished Jewellery items containing other non-metal materials (i.e., stones, enamel, etc.).

For metal only items:

• If the gram weight is 5% below stated weight, it will pass verification.
• If the gram weight is 5-10% below stated weight, it will require buyer approval. If a buyer rejects, the item will be returned to the seller.
• If the gram weight is 10% or more below the stated weight, the item will be returned to the seller.

Metal purity

The following metals and metal purities are eligible for verification.

Please note, resizing an item may result in undisclosed composition and colour variation variances (i.e., metal alloys used to modify size may affect metal purity).

Silver purity conversion chart

Silver must be at least 92.5%+ Ster., Solid Silver or Sterling Silver.

Purity less than 92.5% silver cannot be marked as Ster., Solid Silver and/or Sterling Silver unless the item is a coin or coin silver having a minimum purity of 90% or more.

Tolerance: Please note there is no negative tolerance on purity.

Gold purity conversion chart

Gold must be at least 9ct to be eligible

Tolerance: Please note there is no negative tolerance on purity

Platinum purity conversion chart

PLATINUM = Pt., Plat or Platinum if preceded by a number indicating parts per thousand of pure Platinum (95%+ purity does not require a number preceding mark).

Please note, purity range below 850 will not be verified.

Tolerance: Please note there is no negative tolerance on purity.

Palladium purity conversion chart

Palladium = Pall., Pd. or Palladium if preceded by a number indicating parts per thousand of pure Platinum.

Tolerance: 1% or 10 parts per thousand. For example, if the listing states 950 fineness, eBay will pass a testing result of 940 fineness but will fail a testing result of 939 fineness.

Please note, purity range below 500 will not be verified.

Tolerance: Please note there is no negative tolerance on purity.