Yaozhou kilns originated during the Tang dynasty in Huangbao town, Tonguan prefecture, Shanxi Province. Yaozhou wares had many varieties--white, green, black and splash glaze porcelains.  During the Five Dynasties and Song, Yaozhou kilns specialised in greenwares (celadon) and became an important producer in the north. Yaozhou wares showed great varieties, including bowls, dishes, plates, cups, boxes, pillows, vases, ewers, lamps, burners, inkstone, water droppers, Chinese chess pieces (Weiqi) etc. as well as large quantities of porcelain sculptures of sheep, dogs, horses, lions, dwarfs, Buddhist deities, etc. 

Yaozhou wares were famous for the carved, incised and molded motifs. The lines were strong, deeply cut, firm and beveled along the outline of the motifs.  Under the green glaze, the motifs can be seen clearly.  The dark outline where the glaze gathered contrasts well with the lightly glazed surface of the motifs. The body is fine grained and grayish white, contracting tightly in firing.  The footring, where the exposed clay is often a scorched red color.  The glaze color is an olive green ranging in tone from dark to light, but without any bluish tinge.  The glaze has a high transparency, glossy and thin.

Due to its fame and high commercial value, in recent years many Yaozhou fakes have appeared in the market.  In fact, the fakes are getting better and look convincingly like the genuine stuff.  Below is an imitation Yaozhou bowl with molded design of two cranes surrounded by clouds.  In many aspects it is very close to the genuine one.  On the surface, the olive green glaze looks correct, the scorched red marks are present on the base and the motif is well-molded and clear. 
 
 

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However, if we compare it with the shards of genuine Yaozhou wares below, several discrepancies could be observed:
 

• the glaze of the imitation looks sticky, rough and feels sticky (picture 4).  The glaze on a genuine piece is smooth and glossy (study the glaze of the shards).  It is very likely the the glaze on the fake has been chemically treated to look old and weathered.
• the glaze of the fake has many patches and spots (picture 4). On the genuine piece, the glaze is clear.

• the scorched red marks on the base of the fake looks wet.  Whereas on the genuine ones, the scorched mark appears dry. 

• on the base of the fake (picture 2), there are some blackish grits.  On the genuine ones, such black grits are not present.  On the genuine pieces, the grits are usually grayish white in color (picture 8). 

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Picture 7	Picture 8