Pre-Tested^® is the name of Grumbacher's professional range of oil colors. It's also Grumbacher's flagship. It's the product that, more than any other, represents the way Grumbacher does business: with care, precision, attention to detail -- taking nothing for granted. On a more specific level, it means simply the finest pigments the world can offer, milled in select alkali-refined linseed oil for the professional artist. Pre-Tested stands for optimal color development, high chroma, superior tinting strength, excellent adhesion, outstanding working properties and archival quality.

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Flake White
A permanent, very heavily bodied, opaque, warm white. Having a reputation as the most permanent of all whites. Flake white is ideal for heavy impasto applications or where several layers of color must be built up.
Zinc White
A permanent, heavily bodied, semi-opaque, cool white. Designed especially for brilliant clear tints with all oil colors and excellent for glazing.
Titanium White (Original Formula)
A permanent, heavy-bodied, versatile, opaque, pure white-neutral in hue. Ideal for all applications where great opacity is required. This is the strongest tinting white.
Titanium White (Soft Formula)
A permanent soft-bodied, opaque, non-yellowing Titanium White ground in poppyseed and sunflower oils. Also recommended for fluid wet-in-wet techniques.
Suberba (Titanium White)
A medium bodied, premium quality, non-yellowing, highly pigmented opaque titanium white. Ground in traditional walnut and poppyseed oils.
MG® Underpainting White
A permanent heavy bodied, quick drying titanium white for underpainting. Extremely useful for creating surface textures. Should be use on rigid surfaces only.

Everything Grumbacher makes is tested again and again at every stage of its existence. Their time-proven formulas are fine-tuned through independent laboratory tests as well as hands-on trial by professional artists. Grumbacher specifies the best ingredients available, putting every new one through a rigorous selection process. Grumbacher tests samples of each and every batch of raw material before they allow their vendors to make shipments. On the factory floor, Grumbacher samples batches in the process. And finally, even after their products are in the field, Grumbacher continues to track batches and test for quality, performance and shelf life.