(1) Varnish is a soft contaminant composed of lubricant degradation by-products that are less than 1 micron in size and is not measured by traditional particle count.
(2) Varnish deposit is a thin-orange, brown or black insoluble film deposit occurring on internal of lubricant systems.
(3) Varnish is a high molecular weight substance that is unstable in oil.
(4) Varnish deposit is unable to remove by mechanical filtration.
