Nearly 200 formulations were designed and tested. Out of all the compositions, only two were finally selected thanks to the correct achievement of desired properties in terms of tarnishing resistance, mechanical properties and cost
2000 hours totally dedicated to this project from June 2014 till February 2016.
In our laboratory, more than 100 kg of fine silver were used for tests related to SILNOVA® project, before any industrial test started. After that, casting sessions were performed, for a total number of 100 flasks castings, and more than 50 kg of alloy were produced in sheet and bar form.
Total 400 samples for evaluation of internal porosity and surface quality through cross section analysis; 1600 images captured during this investigation. More than 250 hardness measurements in the as cast state. Total 50 age hardening profiles done summing up to other 200 hardness measurements. Total 50 determinations of crystal grains in the as cast state.
40 sessions of accelerated tarnishing test were performed; in 30 sessions the two “screening test” (TAA + Perspiration test) were performed on lab samples; in the remaining 10 sessions all the six selected reference tests were performed, including finished jewellery pieces like rings, plates, chains.
3 jewelry manufacturing companies (for production of samples and industrial scale tests).
3 Legor Group branches (employees using bracelets for real-life tests).
No alloy in the jewelry Market has till date undergone so many different corrosion tests, and in such harsh testing conditions. Our benchmark to this concern was that of the fashion accessory industry, in which the tests we used are well known.
No other real-life study in the jewelry market has been conducted with such a large amount of data and participants from different countries for such a long time, giving strength and demonstrating our claims.
SILNOVA® is the result of a systematic documentation process, never used before within this sector, that scientifically combines laboratory tests with real-life tests.
The first test involved 6 people in 3 different countries for 9 months of duration, and periodic control was done on each of the bracelets. The same kind of test was then repeated on a larger amount of users for 9 months as well, using only a single object alloy for each of the users.
Real life test was performed by assembling 6 bracelets composed of beads made with 6 different silver alloys and with 2 gold alloys (yellow and white color) at title 375‰. All the beads were made by lost wax casting and submitted to a standard polishing process.
No passivation or galvanic deposition were applied on any of the items. All the beads were submitted to a thermal treatment from the as cast state in order to increase the hardness and to improve the scratch resistance as much as possible.
The purpose of the test was to evaluate the corrosion resistance of the bracelet during the normal use in the real life.
We involved the Legor Group branches and dealers in Bangkok, Mumbai and New York.
We chose testers with different work activities, who used to live in totally different conditions in terms of humidity and temperature. We have monitored our silver alloy reactions also during their leisure time sport activities. The aim was to gather photographic documentation which was comparable and closer to reality as much as possible, over a period of at least one year.
An impressive R&D project, lasted more than 3 years, that has seen 186 plausible formulations subjected to thousands of laboratory tests, and to the tests of the real life.