It's just one of the styles available to workshoppers. Adds a metallic look like Patina, but uses the 4 color altered color space that Spray-Paint and Hydrographic use. Most importantly, making a skin with that in mind opens up the option for tri-planar projection on to the model, so the pattern doesn't break up along the different UV islands.

It does have its downsides, for one the color space is more limited and difficult to convert to from a traditional RGB color space. I found the easiest way was to work in the same way I would mix colors traditionally then testing ingame to see how they were coming out (add a little blue, a little red, etc). On top of that it introduces a little artifacting in gradients, so you generally have to work with hard edges and solid colors.

http://blog.counter-strike.net/workshop/finishes/

Originally posted by KC Sir:

It's just one of the styles available to workshoppers. Adds a metallic look like Patina, but uses the 4 color altered color space that Spray-Paint and Hydrographic use. Most importantly, making a skin with that in mind opens up the option for tri-planar projection on to the model, so the pattern doesn't break up along the different UV islands.

It does have its downsides, for one the color space is more limited and difficult to convert to from a traditional RGB color space. I found the easiest way was to work in the same way I would mix colors traditionally then testing ingame to see how they were coming out (add a little blue, a little red, etc). On top of that it introduces a little artifacting in gradients, so you generally have to work with hard edges and solid colors.

http://blog.counter-strike.net/workshop/finishes/

Couldn't get a better and more detailed answer,you helped me with my question more than enough,thank you very much ^^