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FAQ Here are some of our most asked questions - if you have others I will happily try and answer ..
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| What does "Synthetic" really mean ? The array of synthetic stones around can confuse anyone, if you add in terms like "simulants", "lab-grown", "lab-created" and "imitation" and it's enough to make you want to tear your hair out. What follows is a quick explanation of the terms and what they mean to us at the sharp end.
Imitation : - could be made of anything ... paste, plastic, glass etc .... usually best kept away from
Simulants : - simulants are synthetic stones with the same colour as the stone they are simulating.Thet are usally spinels or corundums. For example a SYN Topaz (SYN is the prefix indicating a synthetic and must be used when refering to them) will probably be a man made spinel coloured the same colour as a Topaz. These stones look exactly like the real thing but DO NOT have the same chemical/molecular make up of the real thing. Although they are made in a lab, they should not normally be called "lab-grown"
Lab-grown/created : - these are stone which DO have the same chemical/molecular make up of the real thing, but are man made rather than naturally occuring. In most cases you will come across they will be corundums (the ruby/sapphire family). So in our stock the SYN sapphires have the same hardness, chemical make-up etc. as their naturally occuring counter-parts so are termed "lab-grown". By the strict definition spinels when made in one of their natural colours and sold as spinels would be classed lab-grown rather than a simulant
In real terms the distinction makes little difference to us as long as they can be fired with good result which both the Simulants and the Lab-grown do ( for the most part ).
Lastly and perversely, the only stone you may have trouble with is a green one. For some reason green stones of whatever nature seem to dislike the firing process. It may be something to do with the oxide colourant being more suspectible to heat. |
| What is PMC ? PMC (or Precious Metal Clay) is a putty-like compound of super-fine silver particles and a water/organic binder that can be moulded as required. When fired ( using a kiln, hand torch or "hot pot" this substance burns off the organics leaving silver (99% silver which is purer than sterling silver). Other silver elements, glass and synthetic stones can all be used to embellish the silver and a variety of surface finishing techniques can be used to create further colour and texture effects. The only limits are your imagination. Available in silver and gold, and in clay, extrudable syringe, paper and paste formats |
| What is Art Clay ? Art Clay is a very similar material to PMC and works on the same principles. Art Clay also comes in a "slow dry" form, which allows you more time to work with the clay before is starts drying out and becomes brittle. Available in silver and gold, and in clay, extrudable syringe, paper and paste formats. |
| What is a spinel ? Spinels : I am adding this section as many people will not recognise the terms imediately. Spinels are naturally occuring gemstones than can occur in a variety of colours. Spinels are very close to rubies chemically speaking, but are closer to diamonds in terms of structure - so proper gemstones, just not so well known - or mistaken for other things. To make things even more confusing many substantial red gems that we know of as rubies are in fact red spinels, the two are so similar. The best example of this is the Black Princes ruby in the British Imperial State Crown is really a red spinel. Ironically some of the coloured spinels are rarer than either saphhires or rubies. |
| Can I fire these stones ? All the gem colours here have been tested to 900 degees C. My own experience is that the stones work fine with PMC+ and PMC3 at normal working temperatures. I would NOT recommend use with PMC regular, the stones may well be fine only to crack later. My feeling is that the combination of high temperature, long soak time, and the larger contraction of the PMC puts the stones under significantly higher stress, whereas with shorter soaks and less contraction the stones can easily withstand the pressure.
PLEASE NOTE I HIGHLY RECOMMEND YOU DO NOT "CRASH COOL" ANY PIECE CONTAINING A SYNTHETIC STONE. Virtually every stone experiences a colour change at high temperature, but returns to its usual colour on cooling. Crash cooling can "freeze" the colour change in the stone. ALWAYS ALLOW TO AIR COOL... or even better leave in the kiln when fired and simply open the door to help the cooling process.
If firing with a torch, move the torch over the surface of the PMC/ArtClay and do not direct the heat at the stone. |
| What are Glass enamels Enamels are minute grains of glass that melt quickly (2-3 mins) at around 800C typically. At this temperature they fuse with the glass forming interest colour highlights if transparent and more solid colour if opaque. Opaques used thinkly become semi-transparent.
The enamels offered here are clean 80 mesh powders. Please ensure you buy the correct enamels... the metals ones are for use on silver, gold, copper and brass but NOT steels. The glass enamels are for use with art glass (Bullseye, Spectrum).
80 mesh refers to size of mesh that will only just allow a grain to pass... so 80 mesh grains will contain particles up that size. 80 Mesh is finer than castor sugar, but not as fine as icing sugar.
The enamels here are lead-free, but not all are...please check this before buying anywhere else. Safety precautions that should be taken include; should be used with face mask, wash hands after using, do not eat ot smoke while using.
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| What are Metal Enamels ? Enamels are minute grains of glass that melt quickly (2-3 mins) at around 800C typically. At this temperature they fuse with the metal clay and form a colourful glossy surface. They can be used to make many pieces typically ; key ring fobs, cuff links, and other jewellery, but also coat ovens, breadbins, kettles and so on.
The enamels offered here are clean 80 mesh powders. Please ensure you buy the correct enamels... the metals ones are for use on silver, gold, copper and brass but NOT steels.
80 mesh refers to size of mesh that will only just allow a grain to pass... so 80 mesh grains will contain particles up that size. 80 Mesh is finer than castor sugar, but not as fine as icing sugar.
The enamels here are lead-free, but not all are...please check this before buying anywhere else. Safety precautions that should be taken include; should be used with face mask, wash hands after using, do not eat ot smoke while using.
Metal enamels are similar ro glass enamels we sell are suitable for use on copper, silver and gold but NOT advised for steel. They are ground to 80 mesh and should be washed before use and can be used wet, dry or in a gum solution. Fired times are from 3-5 minutes at around 800C |
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