In a world first, GRS has carried out extensive research and development to be able to provide the industry a "Respirable Silica Free" product with the same high level of casting quality and usability as a traditional silica based investment powder.

In April 2019 we achieved our goal and have applied for a Patent to cover this new technology that enables the production of an Investment Powder that does not contain Respirable Crystalline Silica (RCS).

X-SIL technology investment powder can be used like for like in place of traditional investment powders in terms of usage procedures, water ratios, mixing equipment, furnaces and burnout cycles, casting machines, casting temperatures and downstream processes.


In order to obtain optimum results the use of a GRS–LE casting flask is beneficial, this flask is made out of a specific grade of stainless steel which improves castability. GRS have also applied for a Patent to cover this new GRS-LE casting flask technology.



How does this compare with traditional silica based investment powder?

Typically, traditional silica based investment powder contains upto 10% Respirable Crystaline Silica. At this level it is classed as STOT RE 2 Hazard.

STOT stands for Specific Target Organ Toxicity which in this case is the respiratory system. In order to control this risk within the working environment, strict dust extraction and respiratory protection control measures must be put in place to comply with the work exposure limit within the country it is being used.

The work exposure limit for RCS in Europe is 0.1mg/m3 over an 8 hour time weighted average (8 hour shift) and in the USA it is 0.05mg/m3.

What about "dust suppressant" products that are marketed by some american companies?

There are some products from the USA that utilise “Dust Suppressant” technology and claim to significantly reduce the airborne dust levels of traditional silica based investment powder products.

Independent testing of a product which utilises this “Dust Suppressant” technology was carried by the Institute of Occupational Medicine (IOM) – Edinburgh, UK which showed that this product contained 5.6% respirable crystalline silica.

This was compared by IOM to other products on the market of similar composition which do not utilise “Dust Suppressant” technology and the results showed respirable crystalline silica content in the range of 5.5 to 6.5%.

The IOM have tested our new X-SIL product independently and confirmed there is no respirable crystalline silica within the product.

Advantages of X-SIL

X-Sil has been developed to be able to cast all non-precious and precious alloys including High Palladium White Gold

It's ease of use is one of it's main advantages. GRS has engineered the product to at least match all cast surfaces finishes from our premium investment powder range without the need for any process or equipment changes.

Additionally, we understand the health of our customers workers is of paramount importance. By utilising X-Sil "Respirable Silica Free" investment powder technology you are protecting your workforce from potential exposure to harmful respirable silica

Please click on below to download the full mixing and burnout instructions


Origins of X-SIL

Goodwin Refractory Services Ltd (GRS) and its sister companies are the global market leader in the manufacture of Investment Casting Powder for the jewellery industry in the world, producing over 65,000 tonnes worldwide per year. GRS is continually investing in R&D and understands the requirement of close customer relationships combined with a world class technical support network. Their complex manufacturing process is backed up by exhaustive raw material control testing and in-house quality control.