Learn about Diamonds – The A to Z Guide to Diamonds & Diamond Jewelry
Before you purchase a diamond or a piece of diamond jewelry, which is not usually a small step or a cheap item to consider, it is a very good idea to know what you are buying. This brief but comprehensive guide will help you learn about diamonds and get you familiar with the terminology of the diamond and jewelry industries. Wherever you decide to buy, it is a good idea to always check the details.
Bookmark this page now for quick future reference.
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9k: 9 karat gold, meaning that 9 of 24 parts of the metal alloy are pure gold, approximately 37.5% pure gold. This is the UK standard.
10k: 10 karat gold, meaning that 10 of 24 parts of the metal alloy are pure gold, approximately 41.5% pure gold.
14k: 14 karat gold, meaning that 14 of 24 parts of the metal alloy are pure gold, approximately 58.5% pure gold. Usually marked "14k" or "585". This is the US standard.
18k: 18 karat gold, meaning that 18 of 24 parts of the metal alloy are pure gold, approximately 75.0% pure gold. Usually marked "18k" or "750".
24k: 24 karat gold, pure gold.
925: Used to mark sterling silver jewelry.
950: Used to mark 95% pure platinum jewelry.
A
Appraisal: A written estimate of the retail replacement of the diamond described. Usually being used for insurance purposes and should be updated every few years. Appraisals are usually given for jewelry as a whole rather than for a loose diamond, but both do exist.
Accents: Small diamonds set in a solitaire ring or another piece of jewelry are referred to as the accents.
B
Bezel facet: On a round brilliant diamond, these are eight large kite-shaped facets on the crown.
Bezel Setting: A way of setting a diamond in a piece of jewelry, but setting the stone by encompassing the entire girdle of the diamond. A semi-bezel setting will mean the diamond is set partly in a bezel setting.
Brilliance: The term used to describe the reflection of white light emitted from the diamond in its “face-up” position. This is the main characteristic that differentiates diamonds from other, less brilliant, gemstones. (No other gemstone has the power to equal the extent of a diamond’s light reflection).
C
Carat: the standard unit of a gemstone’s weight. On carat equals 1/5 of a gram or 1/142 of an ounce. 1 carat=100 points.
Cavity: A type of inclusion consisting of a large or deep opening in a gemstone.
Certification: Sometimes considered the 5th of the 4 C's. Independent certification ensures accurate grading of the 4 C's and therefore guarantees value for money. Some of the leading gemological labs include GIA, HRD, IGI, AGAS and EGL.
Clarity: One of the 4 C's of diamond characteristics. Refers to the type, size and quantity of inclusions or imperfections in the diamond. The higher the clarity of a diamond, the more valuable it is. Not to be confused with color or brilliance, although good clarity can enhance both these parameters. Read more on Diamond Clarity.
Clarity enhancement: Any process used to improve the apparent clarity of a diamond. Clarity enhanced diamonds can include fracture filling, laser drilling heating and cleaning of the stone. Read more on Clarity Enhanced Diamonds.
Cloud: A group of minute to very small, white inclusions which give a “cloudy” appearance.
Color: One of the 4 C's of diamond characteristics. Graded from D (colorless and most desirable) to Z (yellow and less desirable). Read more on Diamond Color.
Crown: The part of the diamond that is above the girdle. It consists of the table facet and the crown facets below the table.
Crystal: A type of inclusion. A crystal is a mineral deposit trapped inside the stone.
Culet: The point at the bottom of a full-cut diamond.
Cut: The way the diamond has been cut will determine its fire and brilliance. The better the cut of the diamond, the more light will reflect out of the face of the diamond. Read more on Diamond Cut.
D
Depth: The distance between the table facet and the culet measured in millimeters.
Dispersion: The fiery, rainbow color-flashes emanating from a diamond. This is white light broken up into the colors of the spectrum.
Durability: This covers extremely thin girdles as well as inclusions that weaken a diamond. Clarity enhanced diamonds are no less durable, however tend to have more natural inclusions that tend to weaken the diamond. The enhancement will not affect the durability but may hide susceptible inclusions.
E
Eternity ring: A diamond ring with an array of diamonds set all around the ring. Eternity rings are used as wedding rings and anniversary bands.
Eye-clean: The term used in clarity –grading: “eye-clean” diamonds should have no inclusions that are visible through the table to the unaided eye.
F
Facet: Polished planes on the surface of a diamond.
Fancy color: Diamonds having color more intense than ‘Z’, as well as diamonds with color other than yellow or brown are considered fancy colored diamonds. These diamonds are graded using different systems.
Fancy shape: Any shape that is not round, also known collectively as "pears". Includes: square princess, radiant, cushion, heart, pear, oval, marquise and others.
Feather: An internal fracture or break in a diamond that looks like a white feather.
Fire: A term referring to dispersion and/or brilliance.
Fluorescence: The property in approximately 50% of all diamonds that makes them glow when exposed to ultraviolet light.
Fracture: A chip or break on a diamond that is not in the direction of a cleavage plane.
Fracture filling: A treatment whereby feathers in a diamond are filled with a clear glass like substance, used to make inclusions less visible to improve the clarity of the diamond. This is a type of clarity enhancement.
G
Girdle: The outer edge, or outline of the diamond’s shape.
Girdle thickness: The measurement describing the girdle thickness is the average distance between the pavilion (lower part) and crown (upper part).
Gold Purity: See above for 9k, 10k, 14, 18k and 24k gold.
H
Hearts and arrows: Also called “H&A”, these are mostly round cut diamonds having superior cutting quality and which are known to show a visual pattern of 8 hearts looking down through the pavilion and 8 arrows when viewing the diamond in the face-up position using the H&A loupe.
I
Ideal cut: A diamond polished to the highest precision and perfection resulting in ideal balance between brilliance and fire.
Inclusion: A naturally occurring imperfection in a diamond.
Invisible setting: A technique used to set a number of diamonds together without visible gold prongs. This setting gives the effect of one large diamond when the small diamonds are set together.
K
Karat: The measurement of gold’s purity, with 24 karat being pure gold. Not to be confused with carat weight of diamonds.
L
Laser drilling: A clarity enhancement technique, whereby a laser is used to drill into to a dark inclusion which is then bleached in order to enhance the inclusion’s appearance.
Loupe: 10x magnifying lens used to examine diamonds.
Luster: The degree to which a diamond reflects light.
M
Mine cut diamond: An ancient form of the brilliant diamond with a cushion shaped outline, high crown, small table, deep pavilion and an extremely large faceted culet.
N
Natural: A small rough diamond portion that can be found on some polished diamonds.
Natural Diamonds: Includes all real diamonds that are mined and not synthetically created.
O
Old European cut diamond: The earliest known form of brilliant cut diamond with a very small table and steep crown.
Optical property: A gem’s intrinsic ability to interact with light.
P
Pave: A jewelry setting technique in which numerous small diamonds are mounted close together to create a glistering diamond crust that covers the whole piece of jewelry and obscures the metal under it.
Pavilion: The lower part of a polished diamond, usually coned-shaped.
Pinpoint: Internal characteristic, minute to very small, usually a whitish dot inside a diamond.
Platinum: A hard metal with excellent durability, white in color.
Polish: The way polishers finish the smoothness of facets on diamonds.
Prongs: Metal (gold, silver, platinum) spikes used to hold the gemstones in place. A prong setting ring refers to the way that the center diamond is held.
R
Rhodium: A white metal from the platinum family, commonly used to plate white gold jewelry to give it a whiter, shinier finish.
S
Scintillation: The small areas of light in a polished stone that flash on and off as the diamond, the observer or lighting moves.
Shank: The shank of a ring is referred to as the side area, also commonly known as the shoulders.
Star facet: One of the eight triangular facets found at the edge of the table facet and pointing to the outline of a brilliant cut diamond.
Solitaire: A type of diamond ring usually including one larger center diamond alone. The diamond itself is also commonly referred to as the solitaire.
Symmetry: Symmetry of facets, and symmetry of the parts of the stone.
T
Table: The largest facet, situated on top of the crown of a diamond.
U
Underside View: Looking at the diamond through the base, rather from the face (table view).
W
White Gold: White gold is a gold alloy made from pure gold, which is yellow, and a mix of white metals, usually including silver, nickel, platinum and palladium. Read more about White Gold.
Wholesale Price List (Rappaport): A price list used by diamond traders to buy and sell diamonds at the wholesale level. The Rappaport diamond price list indicates the going rates at wholesale for every carat weight, color and clarity combination in New York. There are different price lists for "Rounds" and "Pears".
Before you purchase a diamond or a piece of diamond jewelry, which is not usually a small step or a cheap item to consider, it is a very good idea to know what you are buying. This brief but comprehensive guide will help you learn about diamonds and get you familiar with the terminology of the diamond and jewelry industries. Wherever you decide to buy, it is a good idea to always check the details.
Bookmark this page now for quick future reference.
#
9k: 9 karat gold, meaning that 9 of 24 parts of the metal alloy are pure gold, approximately 37.5% pure gold. This is the UK standard.
10k: 10 karat gold, meaning that 10 of 24 parts of the metal alloy are pure gold, approximately 41.5% pure gold.
14k: 14 karat gold, meaning that 14 of 24 parts of the metal alloy are pure gold, approximately 58.5% pure gold. Usually marked "14k" or "585". This is the US standard.
18k: 18 karat gold, meaning that 18 of 24 parts of the metal alloy are pure gold, approximately 75.0% pure gold. Usually marked "18k" or "750".
24k: 24 karat gold, pure gold.
925: Used to mark sterling silver jewelry.
950: Used to mark 95% pure platinum jewelry.
A
Appraisal: A written estimate of the retail replacement of the diamond described. Usually being used for insurance purposes and should be updated every few years. Appraisals are usually given for jewelry as a whole rather than for a loose diamond, but both do exist.
Accents: Small diamonds set in a solitaire ring or another piece of jewelry are referred to as the accents.
B
Bezel facet: On a round brilliant diamond, these are eight large kite-shaped facets on the crown.
Bezel Setting: A way of setting a diamond in a piece of jewelry, but setting the stone by encompassing the entire girdle of the diamond. A semi-bezel setting will mean the diamond is set partly in a bezel setting.
Brilliance: The term used to describe the reflection of white light emitted from the diamond in its “face-up” position. This is the main characteristic that differentiates diamonds from other, less brilliant, gemstones. (No other gemstone has the power to equal the extent of a diamond’s light reflection).
C
Carat: the standard unit of a gemstone’s weight. On carat equals 1/5 of a gram or 1/142 of an ounce. 1 carat=100 points.
Cavity: A type of inclusion consisting of a large or deep opening in a gemstone.
Certification: Sometimes considered the 5th of the 4 C's. Independent certification ensures accurate grading of the 4 C's and therefore guarantees value for money. Some of the leading gemological labs include GIA, HRD, IGI, AGAS and EGL.
Clarity: One of the 4 C's of diamond characteristics. Refers to the type, size and quantity of inclusions or imperfections in the diamond. The higher the clarity of a diamond, the more valuable it is. Not to be confused with color or brilliance, although good clarity can enhance both these parameters. Read more on Diamond Clarity.
Clarity enhancement: Any process used to improve the apparent clarity of a diamond. Clarity enhanced diamonds can include fracture filling, laser drilling heating and cleaning of the stone. Read more on Clarity Enhanced Diamonds.
Cloud: A group of minute to very small, white inclusions which give a “cloudy” appearance.
Color: One of the 4 C's of diamond characteristics. Graded from D (colorless and most desirable) to Z (yellow and less desirable). Read more on Diamond Color.
Crown: The part of the diamond that is above the girdle. It consists of the table facet and the crown facets below the table.
Crystal: A type of inclusion. A crystal is a mineral deposit trapped inside the stone.
Culet: The point at the bottom of a full-cut diamond.
Cut: The way the diamond has been cut will determine its fire and brilliance. The better the cut of the diamond, the more light will reflect out of the face of the diamond. Read more on Diamond Cut.
D
Depth: The distance between the table facet and the culet measured in millimeters.
Dispersion: The fiery, rainbow color-flashes emanating from a diamond. This is white light broken up into the colors of the spectrum.
Durability: This covers extremely thin girdles as well as inclusions that weaken a diamond. Clarity enhanced diamonds are no less durable, however tend to have more natural inclusions that tend to weaken the diamond. The enhancement will not affect the durability but may hide susceptible inclusions.
E
Eternity ring: A diamond ring with an array of diamonds set all around the ring. Eternity rings are used as wedding rings and anniversary bands.
Eye-clean: The term used in clarity –grading: “eye-clean” diamonds should have no inclusions that are visible through the table to the unaided eye.
F
Facet: Polished planes on the surface of a diamond.
Fancy color: Diamonds having color more intense than ‘Z’, as well as diamonds with color other than yellow or brown are considered fancy colored diamonds. These diamonds are graded using different systems.
Fancy shape: Any shape that is not round, also known collectively as "pears". Includes: square princess, radiant, cushion, heart, pear, oval, marquise and others.
Feather: An internal fracture or break in a diamond that looks like a white feather.
Fire: A term referring to dispersion and/or brilliance.
Fluorescence: The property in approximately 50% of all diamonds that makes them glow when exposed to ultraviolet light.
Fracture: A chip or break on a diamond that is not in the direction of a cleavage plane.
Fracture filling: A treatment whereby feathers in a diamond are filled with a clear glass like substance, used to make inclusions less visible to improve the clarity of the diamond. This is a type of clarity enhancement.
G
Girdle: The outer edge, or outline of the diamond’s shape.
Girdle thickness: The measurement describing the girdle thickness is the average distance between the pavilion (lower part) and crown (upper part).
Gold Purity: See above for 9k, 10k, 14, 18k and 24k gold.
H
Hearts and arrows: Also called “H&A”, these are mostly round cut diamonds having superior cutting quality and which are known to show a visual pattern of 8 hearts looking down through the pavilion and 8 arrows when viewing the diamond in the face-up position using the H&A loupe.
I
Ideal cut: A diamond polished to the highest precision and perfection resulting in ideal balance between brilliance and fire.
Inclusion: A naturally occurring imperfection in a diamond.
Invisible setting: A technique used to set a number of diamonds together without visible gold prongs. This setting gives the effect of one large diamond when the small diamonds are set together.
K
Karat: The measurement of gold’s purity, with 24 karat being pure gold. Not to be confused with carat weight of diamonds.
L
Laser drilling: A clarity enhancement technique, whereby a laser is used to drill into to a dark inclusion which is then bleached in order to enhance the inclusion’s appearance.
Loupe: 10x magnifying lens used to examine diamonds.
Luster: The degree to which a diamond reflects light.
M
Mine cut diamond: An ancient form of the brilliant diamond with a cushion shaped outline, high crown, small table, deep pavilion and an extremely large faceted culet.
N
Natural: A small rough diamond portion that can be found on some polished diamonds.
Natural Diamonds: Includes all real diamonds that are mined and not synthetically created.
O
Old European cut diamond: The earliest known form of brilliant cut diamond with a very small table and steep crown.
Optical property: A gem’s intrinsic ability to interact with light.
P
Pave: A jewelry setting technique in which numerous small diamonds are mounted close together to create a glistering diamond crust that covers the whole piece of jewelry and obscures the metal under it.
Pavilion: The lower part of a polished diamond, usually coned-shaped.
Pinpoint: Internal characteristic, minute to very small, usually a whitish dot inside a diamond.
Platinum: A hard metal with excellent durability, white in color.
Polish: The way polishers finish the smoothness of facets on diamonds.
Prongs: Metal (gold, silver, platinum) spikes used to hold the gemstones in place. A prong setting ring refers to the way that the center diamond is held.
R
Rhodium: A white metal from the platinum family, commonly used to plate white gold jewelry to give it a whiter, shinier finish.
S
Scintillation: The small areas of light in a polished stone that flash on and off as the diamond, the observer or lighting moves.
Shank: The shank of a ring is referred to as the side area, also commonly known as the shoulders.
Star facet: One of the eight triangular facets found at the edge of the table facet and pointing to the outline of a brilliant cut diamond.
Solitaire: A type of diamond ring usually including one larger center diamond alone. The diamond itself is also commonly referred to as the solitaire.
Symmetry: Symmetry of facets, and symmetry of the parts of the stone.
T
Table: The largest facet, situated on top of the crown of a diamond.
U
Underside View: Looking at the diamond through the base, rather from the face (table view).
W
White Gold: White gold is a gold alloy made from pure gold, which is yellow, and a mix of white metals, usually including silver, nickel, platinum and palladium. Read more about White Gold.
Wholesale Price List (Rappaport): A price list used by diamond traders to buy and sell diamonds at the wholesale level. The Rappaport diamond price list indicates the going rates at wholesale for every carat weight, color and clarity combination in New York. There are different price lists for "Rounds" and "Pears".
