Azurite Hue

Pigment History: An inexpensive greenish blue, Azurite was the most important pigment in European painting during the Middle Ages and Renaissance until Prussian Blue replaced it in the 18th century. A natural mineral found in many parts of the world in the upper oxidized portions of copper ore deposits; it is often compared to the green pigment Malachite because of its chemical composition. Weaker and less intense than many of the blues we have today, this blend of Phthalo Blue Red Shade, Zinc White and a touch of Raw Umber is also let down with gel to create an interesting color mixture. It creates an earth color blue that doesn’t overpower other colors.
Pigment Classification: Mixture
Chemical Description: Zinc Oxide / Copper Phthalocyanine / Calcined Natural
Iron Oxide containing Manganese
Opacity/Transparency: 5
Lightfastness Rating: I
Permanency: Excellent
Colour Index Name: PW 4 / PB 15:1 / PBr 7
Colour Index Number: 77947 / 74160 / 77492
Munsell Notation Listing:
Hue: 7.0 PB
Value: 3.10
Chroma: 3.1
Spectrophotometer Readings: N/A
Viscosity Range: 20000-27000 CPS
PH Range: 8.7-9.0
Gloss Average: 21.2
CIE L*a*b* Values: L*31.50 a*-4.96 b-14.71
Tint Strength: 85.69

The Lightfastness Ratings included in this chart are provided by the American Society for Testing and Materials (ASTM) in the standard for “Artists’ Acrylic Emulsion Paints”. (ASTM D 5098, Annual Book of Standards, Volume 6.02). Colors with a Lightfastness Rating of I are considered Excellent (“Exc.”) and those with a Lightfastness Rating of II are Very Good (“V.G.”). Where Lightfastness Ratings have not been obtained according to ASTM test protocol, “NA” is indicated in the table. In these cases, data from pigment manufacturers and our own test facilities have been used and an appropriate description assigned under Permanency.

**The identified colors are sensitive to a combination of moisture and UV radiation and are not recommended for outdoor use.

For Opacity/Transparency, we have determined that an eight-point scale is most appropriate for describing the properties of our colors. We have assigned each color in the chart a number from 1 (most opaque) to 8 (most transparent) to indicate the relative opacity/transparency of that color.

The C.I. (Colour Index) Name is an internationally recognized code assigned to a particular “colorant.” The C.I. Name consists of the category (type of dye or pigment), general hue and serial number assigned, based on its chemical constitution. For example, PB 60, Anthraquinone Blue, indicates a specific Pigment Blue. The C.I. Number is a five-digit reference number assigned in the Colour Index based on the chemical structure of a colorant, regardless of usage class.

Notes:
1) The Golden C.P. designation indicates concentrated cadmium pigments (CC).

2) Information about Iridescent and Interference products apply for both Fine and Coarse grades.