Gold purity is measured in karats, while platinum purity is measured in parts per thousand.

• 24 Carat Gold is pure yellow gold.
• 18 Carat Yellow Gold is made by combining three parts pure yellow gold with one part copper and silver alloy.
• 18 Carat White Gold is made by combining three parts pure yellow gold with one part palladium and silver alloy.
• Platinum 950 is made by combining 95% pure platinum with 5% alloying metals for strength and durability.

Carat, in relation to gemstones, is a measurement of weight.

• 1 Gram = 5 Carats.
• 1 Carat is divided into 100 points.

Cut refers to the symmetry, proportions and polish of an Emerald and greatly influences its color, brilliance, visibility of inclusions, weight retention and overall beauty.

The shape depends on the form of the rough Emerald. The precise design varies according to the Emerald’s natural characteristics, the cutter’s experience and personal preferences.

The Pear Shape is a modified brilliant cut combining the graceful curves of an Oval with the defined point of a Marquise. Its elegant teardrop outline and carefully arranged facets produce lively brilliance and flashes of green fire while maximizing the Emerald’s visual size.

• Color: Lee Wasson subjectively classifies Colombian Emeralds into three principal hues of green: Herb Green, Blue Green and Golden Green.
• Tone: The depth of each hue, subjectively graded from 1, the lightest, to 10, the darkest.

Every Colombian Emerald’s color is unique. Its evaluation is subjective and requires years of experience, continuous observation and comparison.

Clarity is affected by inclusions—natural characteristics or foreign materials within the Emerald’s crystalline structure.

Lee Wasson subjectively estimates the quantity and visibility of inclusions as:

• (*) Free of Inclusions.
• (*) Lightly Included 1 to 3.
• (*) Moderately Included 1 to 3.
• (  ) Highly Included 1 to 3.
• (*) Asterisk denotes desirability.

Every Colombian Emerald contains a unique arrangement of inclusions. Their evaluation is subjective and requires years of experience, continuous observation and comparison.

Lee Wasson subjectively determines the approximate percentage of light returned to the observer through internal reflections.

Window: The approximate percentage of light that passes through the bottom or sides of the Emerald.

Extinction: The approximate percentage of dark areas visible within the Emerald.

Every Colombian Emerald is individually cut according to its natural characteristics. Its evaluation is subjective and requires years of experience, continuous observation and comparison.

• Colombia
• Brazil
• Sandawana
• Afghanistan
• Russia
• India
• Pakistan
• North Carolina
• Zambia
• Ethiopia

Cosquez Emeralds are distinguished by their beautiful green color with a subtle golden influence, created by a slightly greater yellow component within the green. Lee Wasson describes this elegant hue as Golden Green. The finest examples combine this warm, distinctive color with attractive crystal and lively brilliance. Color alone does not determine mine origin; the Emerald’s natural inclusions provide important additional evidence.

Inclusions are natural characteristics or foreign materials within an Emerald’s crystalline structure.

Three-phase inclusions consist of a gas bubble, liquid and a crystal enclosed together within the Emerald.

Pyrite, calcite, quartz, parisite, albite, dolomite and shale may also be present and can provide conclusive evidence of natural origin.

Every Colombian Emerald contains a unique arrangement of inclusions. Their evaluation is subjective and requires years of experience, continuous observation and comparison.

Formed naturally within the earth.

A man-made material with essentially the same physical, optical and chemical properties as its natural counterpart.

Lee Wasson identifies surface-reaching inclusions susceptible to clarity enhancement and subjectively evaluates the amount of treatment present as:

• (*) None.
• (*) Minor.
• (*) Moderate.
• (  ) Significant.
• (*) Asterisk denotes desirability.

Clarity enhancement is generally present unless otherwise specified.

Colombian Emeralds may contain surface-reaching inclusions that are traditionally filled with colorless oils or permanent epoxy resins to reduce their visibility and improve the passage of light through the stone.

Carat, in relation to gemstones, is a measurement of weight.

• 1 Gram = 5 Carats.
• 1 Carat is divided into 100 points.