Made to order If the process is 'design led' a plan of manufacture is made to reach the desired outcome
Design led Starts from a concept
Professional jewellery designers and contemporary jewellers create wildly different styles
Mass produced Jewelley that is designed to be reproduced cost effectively
This type of jewellery is usually cast or die-struck and the alloys are chosen for ease of polishing and casting
Wrought platinum Metal that has been forged into shape using hammers and rolling mills Metal that has been worked gains a tighter grain as the metal compresses
Heat treating Metal 'grain' (microscopic) continues to get tighter when it is worked, until it breaks. Most alloys can be heated to reduce the tightness of the grain and soften the metal. All alloys differ in their 'annealing' properties when they are heated
Metal hardness Alloys have a soft and hard rating. In general metal is heated to the desired colour and either quenched or air cooled. It naturally hardens over time and stresses expedite the process
Annealing To soften the alloy with heat, loosening the grain structure
Bespoke Term is derived from the expression 'be spoken' that means the item was spoken for
Setting The process of fastening the diamond into the setting
There are numerous setting styles and some techniques can only be achieved by specialists
Bright cut The process of engraving a polished rim or frame around stone(s).
Bright cutting is done to highlight the rows / set of stones with a polished borders
Pave/micro pave' Diamonds set in row (French - 'path').
A single row of diamonds is often known as grain
Pave' set diamonds are set with tiny grains which hold the stone at the edges. How many grains depends on the pattern or style used. The aim is to provide enough strength without covering too much diamond.
Micro pave' is possible to do under a microscope
Melee small diamonds
Tcw Total carat weight (Tcw) refers to the total weight of every stone
Diamond make The overall quality of the stone. The better the diamond the better its make
Make can be assessed by the facet angles and polish
Square set / Diagonally set The orientation of the longer side a diamond looking from the top
N/S & E/W orientation
N / S - down the finger &
E / W - across the finger
All fine jewellery is stamped with a purity mark. Some items have a makers mark and there are other marks which designate origin
Currently there are a few ways jewellery is marked to show alloy content
Karat stamp & Fineness stamp
The quantity of precious metal are marked as parts per 1000, and / or parts per (24 in gold)
found in Australia are:
Platinum = 950 (95% platinum and other alloys used to increase hardness)
Pure gold = 24k
Gold alloys 18k = .750, 9k = .375
Fine silver = .999
Sterling and other alloys =.925 (Sterling has 0.75% copper)
is currently designated 900 in Australia to avoid confusion
Part or specific alloy markings such as Pt / Pd are often stamped if the alloy includes platinum/palladium and to stipulate that a part is made of Pt/Pd, for example, a platinum coronet and a gold band.
In Australia each precious metal has it's own border. The quantity of precious metal has not been set. That is, .750 itself does not have to be specific for gold (although it always is). Also 900 palladium is set as the typical alloy, but all it means is that there is at least 90% palladium in the alloy.
Australia follows the UK hallmarking standards. For a history of hallmarking in that country, see here (See side bar "platinum explained" etc for more information) NB The borders used in the UK are not the same as Australia
Karat / Carat
Karat (Kt ) is a measure of the purity of gold alloys
carat (ct) is used to refer to the weight of gems and other small objects
Individual mark / makers mark
Personal mark of the craftsman
GSGA marks are traceable through a touchplate when they are registered
The makers stamp / mark provides provenance
Guild marks The Gold and Silversmith Guild of Australia guild mark has a kangaroo logo representing Australia. There are different marks for other countries and regions
Stock gauge Raw alloy. Metal from a refinery comes in various sizes known as stock gauge
Similar terms Hand made - custom made - bespoke - Hand wrought - Made to order - One off
Hand made widely used term meant to suggest the piece was made by hand. It can include pieces that have 'cast' elements in them. Hand made differs from factory made, mass-produced pieces.
Custom made or 'custom designed'. Custom made pieces can be hand made, or cast.
Bespoke the piece has been custom made. This is a more traditional term.
Hand wrought made from stock gauge alloy. The piece has been shaped by hand.
Made to order custom designed
One off Artistic, one of a kind
'Custom made' is similar to 'bespoke' because both terms suggest the piece was produced individually to the customers' taste. Unlike 'hand made', custom made does not necessarily mean that the jewel was produced by hand
Fusing / soldering
Solder is an alloy that melts at a lower temperature than the object. Platinum can be fused by melting the same alloy as the object being joined. Solder fills the join and creates a bond whereas fused joins are solid
Solder can be alloyed to melt at any given melting temperature. Platinum can be fused with a platinum alloy that has a high melting temperature which partially melts the object. This helps provide a solid join and prevents visible solder lines that are left after the polisher removes the softer alloy
Main alloys used
Platinum - Pt950 Ru50 (95% platinum with 5% ruthenium). It is a strong reliable alloy.
White gold - Au750 Pd/Pd/Cu (75% gold, 20%palladium & platinum, & 5% copper). This alloy resists oxidation and has fantastic forging properties. Nickel can be added for tensile strength.
Yellow gold - Au750 or Au375 The typical alloy is gold, copper & silver.
Palladium - Pd950 Ru50 (95%palladium 5% ruthenium)
Palladium - Pd900 Pt100 (adding platinum off cuts) is more like platinum
Platinum group metals
Platinum group metals include: platinum, palladium, ruthenium, osmium, iridium and rhodium
Gray platinum (my term) - ruthenium alloyed platinum, when 'hot annealed' will draw ruthenium to the surface. Ruthenium is a gray metal. Hand forged items that have been annealed many times will have a finer lattice of ruthenium / platinum and appear grayer in some lights. The gray look is a sign of metal hardness
Pro forma - a mock-up made in silver representing a part or the whole piece. They are used to test designs and check for approval. They can be used as master patterns, and they are made heavier than needed to represent platinum
Liquid platinum - Platinum is very reflective and when shaped carefully the light seems to flow along the metal and shimmer in liquid fashion
Platinumsmith - A worker in platinum who makes platinum jewellery. Link
Fine tuning - Part of the manufacturing process in all well made jewellery. The process involves simultaneous filing, sanding and polishing. The process extends to the construction stages in preparing the parts to be later assembled. Fine tuning is part of the construction. Some components are set and finished before joining
Finishing - The polishing process
Platinum is finished is stages
Overall shaping with hammers, dies or hand shaping tools and / or filing
Fine tuning with less coarse files then escarping files
The remaining scratches are removed with 2 grades of emery paper to prepare the surface
The final polish is achieved with various polishing mops, using different grades of abrasive
The best polish is achieved on the bench using a hand piece and tailored polishing mops
The process can take many hours. Most assembled pieces are pre-polished before assembly as platinum does not oxidize and will retain a perfect polish
Platinum alloys can be hardened on the surface for a fine polish. It's more resistant to abrasives than other precious metals. It has a unique quality where the surface absorbs abrasion. This is why platinum doesn't scratch, rather it displaces
Patina - Every alloy ages differently
The way the metal was finished will affect the way that it lasts