A historically important natural black dye related to Logwood, which can create a gorgeous range of purples. NBk1 and NBk2 are distinct but related, and both are rare in pigments. A related color, NBk1, is also described as logwood, which comes from the Bloodwood Tree (Haematoxylum campechianum), also known as campeachy wood. The C.I code for NBk1, Logwood Lake, is 75290 and NBk2, Logwood Logwood Black Lake, is 75291.
Logwood is a red dye that can yield different colors depending on what is combined with it. CAMEO says, "Using a variety of mordants, the red extract can be prepared as a lake ranging in color from dark blue (chromium or copper), violet-blue (alum or tin) to black (iron)."
The Natural Dye Handbook elaborates on its use as a black dye. Before the advent of synthetics, "...Nearly all black cloth was dyed with a combination of logwood and iron, a difficult color to achieve with natural dyes. Logwood by itself is not very lightfast. A pinch of iron will deepen the color dramatically and improve the lightfastness."
However, an interesting story comes to us from the CAMEO archive: "Because of poor lightfastness, Britain banned the use of logwood from 1581 and 1662. The ban was lifted about 100 years later when it was shown that mordents could make the color more stable. Logwood became an important dye because it was inexpensive and covered a wide color range. It is not used as an artist pigment because of poor lightfastness."
According to CAMEO, "Logwood was used in black inks (iron gall ink and bichromate ink) and watercolors. It is still used as a black dye for textiles and leather."
