Print this page

a

Abrasion

Grey edge of a facet, sometimes referred to as chipping in severe cases. The facet edge should be sharp and clean.

Accident

Unforeseen worsening of quality during the manufacturing processes, usually in the form of internal cracks appearing, or existing cracks becoming bigger, resulting in a loss of value.

ACCREDITED BUYER

A category of regular customer introduced in 2015. Accredited Buyers must have the same standard of financial probity as Sightholders but do not need to commit to the same level of spending.

ALLUVIAL MINING

Mining for diamonds that have been carried by wind and water down rivers over millions of years. 

b

Baguette Cut 

Rectangular in shape, with stepped faceting. A simplified Emerald cut.

BBBEE 

The Broad-Based Black Economic Empowerment programme is an economic policy initiated by the South African Government aimed at providing priority economic development opportunities for previously disadvantaged groups in the mainstream economy.

Bearding 

Fine feathers or vezels around the edge of the girdle, often occurring during the bruting process.

BENEFICIATION

The promotion of in-country wealth creation and skills development by supporting diamond-related activities in producer countries.

Bezels 

Main facets on the crown of the stone.

Blocker 

A diamond polisher that specialises in putting the first facets on a diamond.

Blocking 

A light shaping by polishing of the rough diamond to suggest the final model.

Boart 

Very low quality diamond, usually used for industrial purposes. Can be crushed to powder and mixed with fine oil to form a paste and then applied to the scaife.

Borax 

Liquid used to coat the stone while polishing, which protects it from burning.

Bottom Halves 

Sixteen bottom halves positioned each side of the pavilion main facets.

Bourse 

A meeting place where diamond dealers meet to transact business; a trading floor.

Bow-tie 

A dark area across the centre of a fancy shaped stone, common in oval, marquise and pears, detracting from value.

BPP

Best Practice Principles: a set of ethical, social and environmental guidelines by which all De Beers operations and De Beers Sightholders operate. 

Brilliance 

The intensity of the reflections/fire coming from the diamond.

Brilliant Cut (RBC) 

The most popular cut for a round stone, 58 facets. Round Brilliant Cut.

Brillianteering 

The polishing of the stars and halves that gives the stone its brilliance.

Briolette 

A polished model normally exploiting a whole stone. Regular triangular facets are arranged over the whole surface of the rough. Resembling a bead and often drilled at one end for threading.

Bruise 

Crumbling surface on a stone.

Bruting 

The shaping of the girdle by rotating one diamond against another.

Burn Marks 

Made by the scaife on the surface of a facet due to excessive heat or an uneven surface, generally caused during the brillianteering stage. Caused by the iron reacting with the diamond under heat.

c

4Cs

The four main characteristics that define the quality of a polished diamond: carat, colour, cut and clarity.

CAGR

Compound annual growth rate, a year-on-year percentage growth rate over a specified period of time.

Cantle 

To slightly alter or correct the orientation of a facet. As in cantle the table.

CARAT

A unit of mass for diamonds and gemstones, standardised worldwide in the 20th century at exactly one-fifth of a gram (the metric carat). One of the 4Cs.

CARATS PER PIECE

The number of carats in an individual piece of jewellery.

CARE AND MAINTENANCE

A steady state in which mining operations are suspended, though the ability to resume in the future is maintained.

Certificate 

A grading report issued by a Gemmological Authority detailing and pronouncing on a stone's colour/quality/make and size.

Chip 

A small or shallow opening usually on the girdle edge or a smaller sized cleavage (<1.8cts).

Clarity 

A stone's relative position on a flawless to imperfect scale.

Claws 

Part of the dop, which holds and supports a stone during the polishing process.

Cleaving 

The splitting of a stone along the cleavage plain into two or more pieces.

CLICKS AND MORTAR

A type of business model indicating online and offline sales operations, involving a website and a physical store.

Clivage 

Term normally applied to the cheaper qualities of rough, which need to be split before further processing.

Collection 

Term used to describe high colour rough and polished.

COLOURLESS DIAMOND

A diamond’s colour is a result of its composition: colourless diamonds allow more light to pass through than a coloured diamond.

COMPLETELY AUTOMATED RECOVERY PLANT

The completely automated recovery plant, or CARP, treats diamond-containing ore.

CONFLICT DIAMONDS

Mined rough diamonds used to fund rebel and revolutionary activities against legitimate and internationally recognised governments.

Couple 

Two diamonds that roughly match, to form a pair for a piece of jewellery, such as earrings.

Crack Filled 

Cracks are filled with a clear substance to enhance the stone's appearance.

CRATON

An old and stable part of the continental lithosphere that may contain diamonds. Having often survived cycles of merging and rifting of continents, cratons are generally found in the interiors of tectonic plates.

Cring (Ring) 

Specially prepared areas on the scaife, ie for blocking or brillianteering.

CROWN

The upper part of a polished diamond.

CULET

The facet at the point of the pavilion on a polished stone (if present); the pavilion point itself (if the facet is absent); the general region of the pavilion point.

Cut 

The proportions and finish of a polished stone. Cut can also mean make.

CUTTING AND POLISHING

The process of preparing a rough gem-quality diamond so that it can be used in the manufacture of jewellery.

CVD

Chemical Vapour Deposition: a process to create synthetic diamonds.

CVD REACTOR

A machine designed to create synthetic diamonds using the CVD process.

d

DBGSS

De Beers Global Sightholder Sales.

DENSE MEDIA CYCLONE

A device used in the recovery plant to separate the diamondiferous material from waste.

DENSE MEDIUM SEPARATION

Diamonds are heavier than the material that surrounds them. Once the ore has been crushed to a manageable size, it is mixed with a slurry made of finely ground ferrosilicon prepared to a specified density. In the method known as Dense Medium Separation that exploits the relative densities of different materials, we apply centrifugal force to separate out a diamond-rich concentrate.

DER

Diamond Engagement Ring.

DIAMANTAIRES

The French term ‘diamantaire’ (‘diamantair’ in Flemish) is used in the diamond industry to denote a person who possesses diamond-related skills.

DIAMOND

A precious stone consisting of a clear and typically colourless crystalline form of pure carbon, the hardest naturally occurring substance.

DIAMOND DEPOSIT

A body of rock or other mineralisation containing a concentration of diamond of possible economic interest.

DIAMOND DREAM

The allure that diamonds have for consumers on the basis of their association with romance and a sense of the eternal, and the fact that they are seen as a lasting source of value.

DIAMONDIFEROUS

Containing or yielding diamonds.

DIAMOND INSIGHT REPORT

The Diamond Insight Report is an annual written report first published by The De Beers Group of Companies in 2014. The report aims to summarise the outlook and trends across the diamond pipeline. 

DIAMOND JEWELLERY

Jewellery containing diamonds, no matter how big or small, including in combination with other precious or semi-precious stones.

DIAMOND JEWELLERY ACQUISITION

Diamond jewellery received as a gift or self-purchased.

DIAMOND PIPELINE

The industry value chain that runs from consumers and retail stores to jewellery manufacturers, cutters and polishers, back to producers and explorers.

DIAMOND RECYCLING

The sellback or trade-up of previously owned diamonds or diamond jewellery.

DIRECT IMPACT

A direct economic impact arises from the initial increase in economic activity (eg the GVA generated, the additional employment created and the taxes that are contributed to public finances).

Dop 

Attached to the end of a tang, adjustable to angle facets, also holds a pot for thediamond to sit in.

DOWN-HOLE LOGGING

The process of measuring physical, chemical and structural properties of penetrated geological formations using logging tools that are either lowered into the borehole on a wireline cable (wireline logging) or placed just behind the drill bit as part of the drill pipe itself (logging-while-drilling).

DOWNSTREAM

The stage of the diamond value chain that includes jewellery retailing to end consumers.

DTCB

Diamond Trading Company Botswana

e

EBIT

Earnings Before Interest and Tax: an indicator of a company’s profitability, calculated as revenue minus expenses, excluding tax and interest.

Eight-Cut 

The polishing stage just prior to brillianteering. Small sizes can be sold in this state, and called eight cuts.

Elites, SEC A/B non-Elites, Super Elites

Used in relation to the Indian consumer market, the terms refer to consumers according to their household income levels: SEC A/B non-Elites – between US$5,000 and US$35,000; Elites - between US$35,000 and US$70,000; Super Elites – above US$70,000.

Emerald Cut 

Traditionally a cut-cornered, rectangle in shape, but can be square. The facets are elongated and of various sizes.

EMPLOYMENT TAX

Payments to Government arising from payment of remuneration to employees, including wages, salaries and bonuses.

Evidence 

Unpolished areas left on the stone indicating yield has been maximised.

Excellent 

Cut A round brilliant cut made to a high standard of make and finish.

Extra Facet 

Polished onto a stone to reduce or hide a natural or imperfection.

f

FACETS

Flat faces on diamonds. These can be naturally occuring or can be created in the polishing process.

Fancy Colour 

Any usual colour outside serie, e.g. pink, brown, green, blue, orange or dark yellow.

Fancy Shape 

Any shape or cut except a round brilliant.

Feather 

Another word for crack.

FERROSILICON

A ferroalloy which is an alloy of iron and silicon.

FINE JEWELLERY

Jewellery made with precious materials, such as gold or precious and semi-precious stones.

Fire 

Flashes of different spectral colours in diamonds, as a result of despertion, reflection and refraction; scintillation.

First Balance 

The narrowest measurement taken on a stone to determine maximum polished diameter.

Flaw 

A general term used to refer to any internal or external characteristics.

Flawless – FL 

A stone with no internal inclusions or surface blemishes when viewed at 10x magnification.

Fluorescence 

Reaction of a diamond to ultra-violet light. Detracts generally from value in high colours, but can increase value in low colours. Caused by impurities within the atomic lattice.

FULL-TIME EQUIVALENTS (FTE)

FTEs represent the number of people who work on a full-time basis, where persons working less than full-time hours represent a proportion of an FTE determined by the percentage of full-time hours typically worked.

FULLY INTEGRATED SORT HOUSE

At Jwaneng Mine, this is one of the most modern and secure automated recovery and sorting facilities in the world. Its principal advantages are increased security and reduced recovery costs.

FOREVERMARK

Forevermark is the diamond brand from The De Beers Group of Companies. Only one per cent of the world’s diamonds are of sufficient quality to have the Forevermark icon (invisible to the naked eye) inscribed on them. De Beers also sells diamonds via De Beers Diamond Jewellers, an independently managed joint venture with LVMH Moët Hennessy Louis Vuitton.

g

GEM

A cut and polished precious stone fine enough for use in jewellery.

GEM-GRADE, GEM-QUALITY

A rough or manufactured precious stone fine enough for use in jewellery.

GIA

Gemological Institute of America: a US-based non-profit organisation established in 1931 engaged in research, gem identification and grading services as well as a variety of educational programmes worldwide.

GIRDLE

The edge of a diamond, at the widest part. It can be polished, faceted or bruted.

Girdle Marker 

An instrument to draw around the girdle during manufacture to ensure the correct placing of top and bottom facets.

Glassy 

Term used to describe the appearance of a polished stone that has little 'life' usually due to the bottom angles being too flat. Also describes rough crystals.

Gletz 

A crack, sometimes called a feather.

Grade 

Term used to describe the number of carats found per 100 metric tonnes of rock in the recovery process.

Grain 

Direction for polishing, cleaving, sawing.

GRAINERS

Normally refers to smaller stones whose weight is expressed in grains rather than carats (particularly rough stones weighing less than 2.79 carats and polished stones weighing less than 1 carat); in the Diamond Trading Compay, ‘grainers’ refers to stones weighing more than 3 grams but less than 2.79 carats. Stones that are smaller than this are sometimes colloquially referred to as ‘smalls’. 

GRB

Government of the Republic of Botswana

Gross Domestic Product (GDP)

GDP is a basic measure of a country’s overall economic output. As an aggregate measure of production, GDP is equal to the sum of the gross value added of all residential units (ie industries) engaged in production, plus any taxes, and minus any subsidies, on products not included in the value of their outputs.

GROSS VALUE ADDED (GVA)

GVA is a measure of economic activity. It is often referred to as the ‘income from production’ and is broadly equivalent to the wages and profits generated by a particular economic activity, or total output (revenues) minus intermediate costs. GVA differs from GDP in that it does not include net taxes and subsidies levied on products.

h

Halves

There are sixteen top halves: facets put around the edge of the crown and sixteen bottom halves.

Heart Shaped Cut 

A variation of a round stone. A "V" shaped groove is made in the edge of the stone to give the heart shaped appearance. The width is approximately equal to the length.

Hearts & Arrows 

Round Brilliant made to precise proportions. The facets appear through the table as eight arrows and from the bottom, eight hearts.

Hoek / Hook 

Eight main facets (4 top / 4 bottom).

Hong Kong Make

Preferred in Hong Kong/China for the larger table. Usually in medium to low colours and good quality.

HPHT

High Pressure High Temperature: a process to create and treat synthetic diamonds.

i

Ideal Cut 

Form of round brilliant professing to have ideal proportions. First branded by Lazar Kaplan.

IIDGR

The International Institute of Diamond Grading and Research is the part of De Beers that offers polished diamond grading services and through which De Beers’ diamond verification instruments are sold.

IMPACT BENEFIT AGREEMENT (IBA)

IBAs are formal contracts outlining the impacts of the project, the commitment and responsibilities of both parties, and how the associated Aboriginal community will share in benefits of the operation through employment and economic development.

Imperfect – I 

Inclusions are very easily seen through the table with a 10x loupe, they can also affect the brilliance of the stone. The first quality where inclusions can be seen with the naked eye.

INCLUSIONS

Any naturally occurring material inside a diamond (including internal cavities and cracks).

Indented natural 

A natural that penetrates the surface of the stone.

INDEPENDENTS

Single stand-alone stores as distinct from retail chains of multiple stores. 

INDICATOR MINERALS

Minerals used to help locate diamond deposits. They are minerals that are characteristic of kimberlite but usually more abundant than diamonds (and therefore easier to find). Indicators form in association with diamonds in the kimberlite and are scattered over a wide area by erosion. By tracing these indicators, the source of the kimberlite may also be found.

INDIRECT IMPACT

As producers increase their output, there will be an increase in the demands they place on their suppliers, which continues down the supply chain.

INDUCED IMPACT

As a result of the direct and indirect effects, increased employment results in an increase in household incomes throughout the economy. A proportion of this increased income will be re-spent on final goods and services, thus generating further economic impacts.

INDUSTRIAL DIAMONDS

Natural diamonds and synthetics used for non-jewellery purposes in manufacturing processes across various industries (oil and gas, precision tools, mining etc).

INR

Abbreviation for the currency Indian rupee.

Internal Graining 

Area in a stone with a deformed crystal structure, associated with plastic deformation; can effect translucency.

Internally Flawless 

IF stones have no internal inclusions only slight surface blemishes visible under 10x loupe.

INTERNATIONAL GEMOLOGICAL INSTITUTE

A diamond, coloured stone and jewellery certification organisation established in 1975 with headquarters in Antwerp.

j

Japanese Make 

Term of rounds popular in Japan for their smaller table. Normally made in good colour and quality. Usually polished for "excellent" proportions.

k

Kaps 

Pieces cleaved or lasered from a larger stone.

Kerf 

A 'V' shaped groove made in a rough diamond originally by hand using another diamond, or lasered on a cleaving grain, prior to splitting the diamond in two.

KIMBERLEY PROCESS (KP)

Intergovernmental rough diamond certification scheme aimed at preventing conflict diamonds entering the legitimate diamond value chain.

KIMBERLITE

An intrusive igneous rock that is sometimes diamondiferous. It is unevenly grained, containing minerals such as olivine, phlogopite and pyrope garnet, cemented with a groundmass consisting of minerals such as serpentine, calcite and chromate. Kimberlite occurs in the earth’s crust in vertical structures known as kimberlite pipes.

Kites 

A kite shaped facet is formed from a bezel after the star and top half facets are made.

l

LOUPE

A magnifying glass, usually magnifying 10 times (10x). A ‘hand loupe’ is hand-held, whereas a ‘head loupe’ has two lenses (one for each eye, providing stereoscopic vision) mounted on a frame worn on the head. For practical reasons, the standard magnification for a diamond sorter’s head loupe is 3.5x rather than 10x.

m

MACRODIAMOND

A recovered rough diamond greater than 0.5mm.

MELÉE

A term used to describe small cut and polished diamonds. The diamond weight for melée diamonds ranges from as low as 0.001 carats (1,000th/carat) to 0.18 carats.

MICRODIAMOND

A very small rough diamond, less than 0.5mm.

MIDSTREAM

The stage of the diamond value chain that includes sales of rough diamonds, cutting and polishing, primary and secondary sales of polished diamonds, and jewellery manufacturing.

n

NATURAL DIAMOND

A diamond formed naturally over millions of years in the earth’s crust.

NEAR GEM QUALITY

A quality band between gem-quality and industrial diamonds.

o

ODC

Okavango Diamond Company.

ONSITE CONTRACTORS

Onsite contractors represent indirect employees working at a particular mining site.

OPEN-PIT MINING

Mining from the surface to expose the ore below.

p

PAVILION

The lower part of a polished gem, below the girdle.

PAYMENTS TO GOVERNMENT

Payments in respect of taxes, including both taxes borne and taxes collected.

PLEISTOCENE

The geological period lasting from about 2.6 million years ago to 11,700 years ago.

POLISHED

Diamonds that have been polished in preparation for use in jewellery manufacture.

PWP

Polished Wholesale Price: a term referring to prices achieved by cutter polishers in cutting centres for polished diamonds.

r

RESERVES

Mineral deposits that can be economically extracted.

RIPPLE EFFECT

Temporary mismatch between supply and demand caused by the de-stocking or re-stocking activities of midstream operators in response to changes in market conditions.

ROIC

Return On Invested Capital: the return on invested capital measure gives a sense of how well a company is using its money to generate returns. Comparing a company’s ROIC with its cost of capital reveals whether invested capital has been used effectively.

ROUGH DIAMOND

A diamond that has been mined but not yet cut and polished in preparation for use in jewellery manufacture.

ROYALTIES AND MINING TAXES

Royalties and mining taxes refer to payments to Government in relation to revenue, production or profit generated under licence agreements.

s

SIGHT

An event where customers can inspect and buy diamonds from De Beers.

SIGHTHOLDERS

Term contract rough diamond customers of De Beers.

SIMULANT

A substance used to imitate diamond.

SMALLS

Colloquial term for rough diamonds under three grainers. A grainer is a unit often used in the diamond trade to approximate the weight of a rough diamond; a grain is about 0.25 carats.

SMARTY CAMERA

An in-vehicle Event Data Recorder that makes constant video recordings of a journey. It is designed to reduce risk by encouraging safe driving behaviour and aiding in the process of investigating car accidents.

SOCIAL INVESTMENT

Social investment refers to social contributions paid on a compulsory or voluntary basis, either from allocated budgets or established programmes.

SOLITAIRE

An item of jewellery (for example, a ring) that highlights a single diamond.

SORTING

The process of classifying rough diamonds into a variety of categories based on their natural characteristics, specifically their colour, clarity, carat and model or shape.

SYNTHETIC

A man-made diamond with the same chemical composition, crystal structure and physical properties as its natural counterpart. Where a product is man-made, but has the same structure as a natural counterpart, an accepted description must be used to make clear that the product is man-made. Synthetic is one such description.

t

TABLE

The largest, central octagonal facet on the crown of a polished diamond.

TREATMENT

Any non-natural processes (other than shaping, polishing and surface cleaning) that change, interfere with and/or contaminate the natural appearance, composition or durability of a gemstone. For diamonds, this includes colour treatments (and decolourisation or ‘bleaching’), fracture filling, laser-drilling, irradiation treatment, and coating.

Tier cities

Often used in relation to China and India, this term relates to key characteristics of a city, particularly its population, economic development, regional GDP, transport systems and infrastructure, and/or historical and cultural significance.

u

UNDISCLOSED SYNTHETIC

A synthetic diamond that has been falsely passed off a natural gem.

UPSTREAM

The stage of the diamond value chain that includes rough-diamond exploration and production.

v

Vezel

Flemish for surface crack.

Very slightly included – VS

VS stones have imperfections that are not easily seen. Small clouds and feathers are typical.

Very Very slightly included - VVS

VVS stones have slight imperfections that are difficult to see. Imperfections would be only visible from the pavilion or small enough to be removed by repolishing.

w

WACC

Weighted Average Cost of Capital: a calculation of a company’s cost of capital in which each category of capital is proportionately weighted. All capital sources – common stock, preferred stock, bonds and any other long-term debt – are included in a WACC calculation.

WAGES AND SALARIES

Wages typically relate to employment based on hourly rate of pay, while salaries are typically agreed on an annual basis. This means salary payments do not tend to vary based on short-term (eg weekly/monthly) fluctuations in hours worked, while wages would.

Wass 

A flemish word meaning grain: either sawing or cleaving.

WHOLESALER

An organisation that buys polished diamonds in order to distribute them to jewellery manufacturers and retailers.

Windowing 

Very small facets polished on to the rough diamond to see more clearly into the stone.

y

Yield 

The weight of a polished stone achieved from the rough normally expressed as a percentage.

z

Zero Plane

In polishing it is flat on the three point grain. A facet can not be polished on this grain.

Zooting

Smoothing of a facet on the scaife to a mirror finish.