Azurite is found in connection with malachite because they are chemically related. Visual examination with a microscope confirmed the presence of azurite in the Yuan dynasty scroll painting ‘Horse and Groom’: in the collar of the groom’s robe.

                                                                ‘Horse and Groom’

                                Acc. No. F1945.32, Freer Gallery of Art.

Observations under the microscope:

Azurite is clearly identifiable under the microscope.

The scroll was microscopically tested in July 1970 by Fitzhugh, but she only noted in the museum records that vermilion is recognized. The scroll was examined again in 1980 by John Winter, and his report in the museum records contains an XRD-result confirming azurite and vermilion. Azurite was not found in any of my samples from the Tang Murals.

Azurite is the blue form of a mineral, and malachite is the green variety. Both minerals can be ground as a painter's pigment. The colour is partly defined by the size of the grains. In Europe, this mineral has been used since the Renaissance, and was called azure blue, copper lazuur, and mountain blue. In an oil binder azurite easily oxidizes to green, looking exactly like its 'brother' malachite. Even with the fresco technique, a green discoloring can arise from humidity. Malachite and azurite are both copper carbonate: see also the entry for malachite.

                                   

                                          Azurite cristals on a matrix with some malachite.

These are Yu Fei’an’s comments on azurite: 中国绘画颜色的研究, Zhongguo huihua yanse de yanjui, The research of Chinese Painting Colours, Beijing, 1957

“In the Liang dynasty Tao Hongjing 陶宏景 (painter and physician, 452 – 536) wrote in his book Attached notes to the Famous Physicians (Mingyi bielu, 名医别录): ‘Azurite goes hand-in-hand with copper.’ This conforms to the view of present-day scientists.

The five forms are Azurite, Flat blue, Layered Blue, White blue and Grain blue. These are all poisonous.

Azurite

The lumps look like bayberries. Su Song (稣颂 ± 1058) from the Song dynasty says:” It is found in Raozhou and Xinzhou, the form is like bayberries that are hollow; pound it flat to form a syrup; it is hard to find. (See the Illustrated Materia Medica, Tujing Ben Cao, 1596, Li Shizhen). Painters and physicians love to talk about azurite, they say it comes from gold mines or copper mines. I (Yu Fei’an) have only seen it being mined in Sichuan. There its form resembles berries of azurite, there are crevasses in the surface but there is certainly no syrup, and it is also not very useful.

Flat blue

Flat blue comes from Yunnan and Burma. The Yunnan variety is called Yunnan blue: 滇青, Dianqing. The Burma variety is called Burma blue: 甸青, Dianqing. This is the Meihuapian mentioned by Wang Gai in the Jieziyuan Huazhuang in the Qing dynasty. The lumps from Burma are much larger but not as beautiful as the Yunnan lumps.”

The pinyin transcription (and many other transcription-systems) ads more to the problem of translation than it resolves, because of the similarity of ‘dian’ and ‘dian’. Such problems only arrise in an alphabet, since for any

Chinese reader there is a clear difference between the characters for dianqing 滇青, and dianqing, 甸青。

“Layered blue

The layered blue has alternating dark and light layers, or it has only dark layers. Painters prefer the light colored ones. The light color is collected and than ground to powder. The blue deriving from this is called Tianqing, Sky-blue. It is found in Shanxi, Hunan, Sichuan, Xikang and Tibet.

White blue

White blue is also known under the name of jade blue. It comes from Yunnan, Guizhou and Sichuan. It is even lighter than sky blue and does not shine. It is not greatly used by painters.

Grain blue

Grain blue is also known under the name of Buddha-blue and Hui-blue. This pigment stems from the area west of Dunhuang. In the ancient Chinese texts, nobody mentions this. In all the Buddhist paintings and wall paintings grain blue is used, both for the wall paintings in Dunhuang as well as for the Buddhist paintings of the Ming and Qing dynasties. There are two sorts: one is a coarse grain, and the other has finer grains. The coarse-grained variety has both larger and smaller grains, while the fine-grained variety

has finer grains which are not as fine as powder. Every packet holds 48 liang. It is still available in areas such as Xikang, Tibet and Xinjiang. In peasant painting the Tibetan variety is called Tibet blue.”

Xikang: An area in south west China, now part of Sichuan and Tibet.

Liang, 两: a measure of weight 1 jin, 斤, is equal to 16 liang. 1 jin is 500 gram.

The Hui form an ethnic minority group in China, lending their name to this form of blue. Hui blue is also mentioned by Needham as a candidate for blues in the smaltite or cobaltite group. In the Chinese texts that are used for this research I have found no record of this Buddha-blue or grain-blue as described by Yu Fei’an.

Needham: ‘flat blue’ is possibly smaltite or cobaltite.

Needham, J. and Lu Guai-Djen, Science and Civilisation in China, vol 5, Chemistry and chenical technology,part 2, Spagyrical Discovery and Invention: Magisteries of Gold and Immortality, page 169.

Azurite, like cinnabar and malachite, is one of the pigments that can be separated into different layers by the sublimation process described under the entry for cinnabar.

The split bamboo tube with vermilion and malachite separated in three layers: the bottom layers are called ‘ first red’ and ‘first green’.

A list of synonyms for azurite is published

in the Materia Medica [Read and Pak, section IV, 2, p 50]:

Azurite, pianqing, 扁青

Synonyms:

Shiqing, 石青[mineral blue]

Daqing, 大青[big blue]

Lantong, 蓝铜[blue copper]

Modern term:

Lantongkuang, 蓝铜矿[blue copper ore]

Pianqing or Daqing (also called Yangqing) is cobalt or Lapis armenus, a kind of zaffer, or ‘powder blue’, or smalts, prepared by roasting the native arseniuret [sic] of cobalt.

Cambodia is said to yield Pianqing. It contains silica and potash.

Baiqing, 白青

Light-coloured azurite, in round pieces the size of fish eyes.

    Polygonum tinctorum is termed Daqing, 大青，

    This refers to the dye indigo.

Said to be the same as lüqing.

Lüfuqing, 绿虜青 [green skin blue]

An old name for an azurite remedy for insect and snake bites.

Synonyms:

Tuiqing, 推青[push blue]

Tuishi, 推石[push mineral]

Bishiqing, 碧石青[gem stone blue]

An indefinite substance from azurite, similar to the above.

Another form of green pigment which differs in chemical composition from the minerals malachite and azurite, is found in the Materia Medica [ section V, p 72]:

Lüfan, 绿矾

Ferrous sulphate, green vitriol, copperas.

    Synonyms:

    Heifan, 黑矾[black vitriol]

    Zaofan, 皂矾[black vitriol]

    Qingfan, 青矾[black vitriol]

    Jiangfan, 耩矾[drill vitriol]

    Fanhong, 矾红[vitriol red]

    Qingfanyin, 青矾银[black vitriol silver]

    Yatieliusuan, 亚铁流酸[ferrous sulphate]

    Modern terms:

    Liusuanditie, 硫酸低铁[sulphate low grade iron]

    Tieliuqiangfan, 铁流强矾[molten iron strong vitriol]

    Liusuantie, 硫酸铁[sulphate iron]

It is sold in broken masses of green crystals of great purity, and little disposition to oxidize, even in the damp atmosphere of China. It is made from sulphurous coal with hepatic iron pyrites, and allowing spontaneous chemical action to take place, the heap being plastered over with mortar to exclude the air. At Changdefu in Henan sulphate of iron is calcined to produce the sesquioxide of iron used as a pigment.

Peking sample70:

SO4 35,4 %,

H2O 38,3%

Metals Fe and a trace of Na

Contains traces of chloride (N). It is copper sulphate (hu). Acetate of copper also termed Lüfan.

Synonyms Tanfan, see shitan, 石瞻。

Fanhong is literally roseate alum, merely ferrous sulfate.

Jiangfan also is merely sulfate of iron, decomposed to a red powder by prolonged heating.

Fan is best translated as a salt. It was adopted for many years in modern chemistry as the equivalent of the suffix –ATE applied to salts.

Used as a dye and as a fertilizer in Hangzhou. 70.000 piculs exported in 1924. It is manufactured today In the provinces Hunan, Sichuan and Anhui. The best grade is called mianfan, 面矾. The lowest grade is difan, 低矾.

Note that this citation including the sample is from Read and Pak, they only give chemical terms in connection with their samples, and not for any other terms. [Read and Pak, section V, p 72].

This might be connected to the material that Shen Gua was already discussing in the twelfth century; a copper sulphate that could have been used for painting. However, Shen implies another, more lucid interpretation [Shen Gua, 梦溪笔谈, Mengxi bitan, Brush notes from the Dream stream, Zhonghua shuju, Xianggang, 1975, scroll 25, section 455, p 248]:

“Kuquan, 库券, Tong, 铜

In Yanshanxian in the district Xinzhou is an acrid source that flows into a mountain stream. If you scoop up the water and boil it down, it becomes copper sulphate, and if you cook this copper sulphate, it becomes copper; if you boil down the copper sulphate in an iron kettle after a long period it will change into copper as well. That water can produce copper and that matter is transformed, is this not inconceivable? According to the Huangdi Suwen: "Heaven has five phases, the earth has five phases, the spirit of the earth is the 'damp' of heaven: earth can bring forth metal and stone, so damp can also bring forth metal and stone." This is the proof. If water drips on an underground stone, stalactites and stalagmites are formed on the place it drips. If at the Spring equinox or at the Autumn equinox water is scoped from a spring, stone flowers will form. Under the silk marshes yinjingshi, 银精石 [silver-extract mineral] is formed. Both are made of damp. Just as the spirit of wood becomes wind in heaven, when the wood brings forth fire, so the wind can bring forth fire, and I say these are the five phases.”