Glossary of Terms
An organic gemstone which is formed from the fossilized resin excreted from pre-historic pine trees which flourished more than 30 million years ago. Amber ranges from golden yellow to golden orange in colour but variations of green and black have also been found. Some variants of Amber gemstone contain remnants of insects, moss, lichen and pine needles from where the stone has formed over time in nature. Its unusual markings and warm, vibrant colours have continually captivated wearers. The Romans were particularly fond of producing Amber jewellery while the coveted gemstone still remains popular today. You can find our collections of Amber jewellery here.
One of the most commonly found fossils from the Jurassic and Cretaceous periods, these snail-like creatures have a ribbed spiral shaped shell and were believed to have lived in our oceans 240-65 million years ago. Fossilised coiled Ammonite shells can be found in Dorset, Somerset and North Yorkshire and inspire fascinating and unusual pieces of Ammonite jewellery.
A combination of two or more metals. For example, rose gold is an alloy of pure gold and copper.
A gemstone cut where the pavilion is square shaped and has long step facets and a large crown. Asscher cut gemstones are sometimes referred to as square Emerald cut.
A gemstone cut where the table is the shape of a long, narrow rectangle bordered by four step cut facets.
A type of brooch in the form of a horizontal bar, often with decoration along its length or set with gemstones at its centre.
The top metal rim or setting that surrounds the cavity which holds a gemstone in place. A bezel can also refer to the outer ring of a watch face. Some watch bezels are uni-directional or bi-directional, meaning they can be moved and aligned for additional function.
One of England’s most rare and beautiful gemstones, Blue John is part of the fluorite family and is well known for its distinctive blue, yellow and purple coloured bandings. Blue John has only ever been found in one hill about three quarters of a mile west of the small town of Castleton in Derbyshire, making it a rare and highly coveted gemstone. Different parts of the hill are characterised by different patterns of colour banding in the Blue John. Each variation of banding is known as a different ‘vein’ and there are currently 15 different veins of Blue John available. You can find more about Blue John and our Blue John jewellery here.
A gemstone cut commonly used on a diamond which boasts many facets of different shapes and sizes to increase the stone’s brilliance. Brilliant cut diamonds are considered to have the most brilliance (sparkle) of all diamond cuts because the increase in facets minimizes the amount of light that escapes from the bottom of the stone. Most brilliant cut diamonds consist of 58 facets, 33 on the crown and 25 on the pavilion.
A gemstone cut with a domed, smooth and rounded surface with no facets. Cabochon cut stones are usually highly polished and have an impressive shine.
The unit of weight for a diamond or gemstone. There are 100 points to every 1 carat.
A style of jewellery setting whereby a row of identically sized and shaped stones sit within two parallel walls of metal and are pushed together to secure the stones in place.
A style of jewellery setting in which the stone is held above the girdle by a series of encircling, vertically projecting prongs or claws. The prongs are pushed over the stone to secure it into place.
The upper part of a cut gemstone. The crown can be found above the girdle and below the table.
A chain constructed of lots of tiny links interlocked with each other.
A style of cutting a gemstone shaped as a square or rectangle with rounded corners. Although they generally have less brilliance than brilliant cut gemstones, cushion cut stones have better fire (the coloured sparkle that you can see when the stone is exposed to light).
The point at the base of a brilliant cut diamond. These appear as a small flat facet on old-cut diamonds.
The final form into which a rough gemstone is shaped. There are several gemstone cuts to choose from including brilliant cut, princess cut, asscher cut, emerald cut etc.
One of the small, flat surfaces of a cut gemstone. Facets come in various shapes and sizes and the many arrangements of the facets depends on the style of cut.
A gemstone’s fire is the coloured sparkle that you see when the stone and its facets are exposed to light. Like the shades seen in a rainbow, diamond fire is caused by light that has been broken down into different colours. Unlike a diamond’s fire, brilliance is the colourless light reflected from the stone.
The most malleable and ductile of all metals, Gold is unalterable by heat and moisture and will never tarnish. Pure gold is too soft for practical use alone and so is alloyed with its purity expressed in carats:
9ct – Is 37.5% or 375 parts out of 1000 pure 24ct gold.
18ct – Is 75% or 750 parts out of 1000 pure 24ct gold.
Alloys of silver, copper and zinc are then added in different quantities for hardness and durability.
The thin band that forms the widest circumference of a brilliant cut stone and that separates the crown above it from the pavilion below.
The mark(s) stamped on some items of gold or silver that attests the purity of the metal. All precious metal jewellery that contains gold, silver, platinum or palladium must be hallmarked in compliance with legally established standards. A hallmark includes a date letter, a maker’s mark and an assay mark to indicate the office that does the assaying.
A gemstone which is set down into the bezel with the top of the stone protruding upwards. The stone in a lap setting is cut back down into a domed shape which sits flush with the top of the bezel.
A type of clasp found on the chains of necklaces and bracelets shaped like a lobster claw, hence its name. A lobster clasp is opened by holding down a small lever and is closed on release by a small spring.
Small cut and faceted stones made from an iron ore called Hematite. Marcasite come in a dark grey, metallic colour, usually seen in conjunction with other stones. When they appear as a cluster, they emit an impressive sparkle.
The Moh’s Scale of Hardness is the most common method used to rank gemstones and minerals according to their hardness. Gemstones ranked 1 are considered the softest while 10 are the hardest. The diamond is the only gemstone to be ranked at 10 making it the hardest known material in the world. Moh’s Scale of Hardness was devised by German mineralogist Friedrich Moh in 1812. You can see where other materials and precious stones rank on Moh’s Scale on the table at the bottom of this page.
MOTHER OF PEARL
Available in white, grey and pink, Mother of Pearl is a shining iridescent substance found in the inner layer of shells. Usually seen in molluscs, oysters and abalones, Mother of Pearl is a soft material with a lustrous and polished finish reminiscent to the iridescence of pearls. The white shells come from Australia, the grey from Indonesia and New Zealand and the pink is a mussel shell from the Mississippi River in USA.
A style of gemstone stone setting in which many small gemstones are set close together in a mass. Many pave settings are used to cover the entire piece and conceal the metal beneath. Pavé comes from the French word ‘to pave’, literally meaning to pave something in diamonds or gemstones.
The part of a brilliant cut diamond found below the girdle and above the culet.
PEAR OR TEARDROP CUT
A style of cutting a gemstone into the shape of a pear or teardrop. The stone has a point at the top and tapers out into a rounded bottom.
A coating of precious metal over another metal base. Plating is also sometimes referred to as vermeil.
The most valuable and rare of all the white metals, Platinum is often very heavy and does not tarnish easily. Its name is derived from the Spanish term platino, meaning "little silver".
A unit of weight for a diamond or other gemstone. There are 100 points to every 1 carat.
POST AND BUTTERFLY
One of the most common clasps on earrings, post and butterfly fastenings consist of a metal disk shaped like a butterfly with a hole in the centre to attach through the post of the earring.
A style of gemstone cutting similar to a brilliant cut diamond but instead in a rounded shape. Princess cut diamonds are sometimes also referred to as Quadrillion or Squarillion cut.
A combination of pure gold and copper to create a rose pink colour. Like white gold, rose gold is an alloy so pure rose gold does not exist.
A style of setting a gemstone whereby metal is pushed over the girdle of the stone to secure it in place.
A very small, round pearl which can be natural or cultured. Seed pearls are usually less than 2mm in diameter.
The method in which a stone or stones are secured into a piece of jewellery. There are a variety of jewellery settings to choose from including channel setting, claw setting, pave setting etc.
A style of cutting a gemstone so that below the table there are a number of sloping, parallel rows of four-sided facets that increase in size as they approach the girdle and then decrease as they descend to the culet, thus giving the impression of steps.
An alloy of silver that when used for jewellery in the UK has a fineness of 0.925 parts silver and 0.075 copper.
Like plating, Vermeil is a method which involves depositing a thin layer of precious metal over another metal base.
Whitby Jet is an organic gemstone made from the fossilised wood of the ancient monkey puzzle tree. Although deposits of Jet have been found in many places around the world, the Jet found along the North Yorkshire coast of Whitby is considered the finest. Whitby Jet is one of the oldest gemstones known to man with pieces of Jet jewellery and ornaments dating back to the Stone Age. However, it was during the Victorian era when Whitby Jet reached its height of popularity. Queen Victoria took to wearing the stone after the death of her husband Prince Albert and from then on the stone and the jewellery it adorns became an overnight sensation. W Hamond is the Original Whitby Jet Store opened in 1860 and it continues to handcraft stunning collection of Whitby Jet jewellery today. You can explore our range of silver and gold Whitby Jet jewellery here.
An alloy of gold with a high percentage of other white metals to make it a pale gold colour. It is then plated with rhodium for a bright white finish.
MOH’S SCALE OF HARDNESS
Named after German mineralogist Friedrich Mohs (1773-1839), the Mohs scale is widely used as a hardness standard for gems and minerals. The concept is simple, employing what is often called the “scratch test.” Once Moh’s determined that diamond was the hardest of all materials, he assigned it his highest possible number - Mohs 10. He then sought the softest mineral he could measure which turned out to be talc and gave it a rating of 1. To establish a relative rating for all the common gems and minerals, Mohs rubbed hundreds of materials together and the one that scratched the other received a higher number on his scale. Knowing this concept helps prevent harder gems from scratching softer stones.