M

Mabe Pearl

Assembled cultured pearls.

Maker’s Mark

The initials or stamp of the maker engraved or stamped on a piece of jewellery.

Malachite

The stone’s name derives from the Greek molochitis lithos meaning ‘mallow-gree stone’, given it’s name due tot the resemblance to the leaves of the mallow plant. It is estimated that malachite had been mined since at least 8000BC and is used as a pigment for green paint as well as in cosmetics.

Mappin & Webb

A famous English silversmith company founded by Jonathan Mappin in 1810.

Marquise

The shape of a cut gemstone or the shape of a design of a ring or other piece of jewellery, credited to King Louis XV of France. The marquise shape is distinctive due to its oval shape, with pointed ends.

Melee

An assortment of small diamonds, usually under 0.20 carats.

Metric Carat

The international unit of measurement for gem weight, see ‘carat’.

Millegrain

A granular relief pattern design on metal, produced using a chisel. The effect produces slightly raised bumps and was often used in antique pieces through to the late Art Deco era.

Mixed Cut

A cutting style that combines brilliant-cut and step-cut facets.

Modern Round Brilliant Cut

In the early 1900s, diamond cutters began to experiment with new techniques. A breakthrough came in 1919 with the introduction of the round brilliant cut. Due to its ability to maximize fire and brilliance, the round brilliant cut has become the standard and most popular way to cut diamonds. Like the old European cut, a round brilliant cut diamond has a circular girdle and 58 facets. However, the round brilliant cut lacks a culet. The round brilliant cut became prevalent during the Art Deco and Retro periods. See The Four C’s for more information.

Mohs Scale

A ‘scale’ with which to compare the hardness of a given gemstone, developed by the mineralogist Freidrich Mohs. Gemstones are ranked from numbers 1-10 with 1 being the softest and 10 the hardest. The scale goes up exponentially.

Moonstone

Part of the Feldspar group – the most abundant minerals found in the Earth.
In the worlds first encyclopedia, written between 20-79 AD by Pliny the Elder, moonstone is referred to as ‘astrions’ meaning ‘star stone’- named so as it possesses a silvery blue or white iridescent sheen. This sheen is called ‘adularescence’ by gemmologists. Moonstone was used extensively during the Art Nouveau era.
Read more

Morganite

A pink coloured variety of the mineral species beryl, alongside emerald and aquamarine. A relatively new gem on the market, most notably promoted by Tiffany & Co in the last century. Read more

Muzo

An area in Colombia that is known as the source of the finest emeralds in the world which possess a deep bluish green colour.