From the observation of these Stradivarius paints, some conclusions can be drawn: firstly, the material formula we are facing has no connection to the paint formula after the Guarneri ç u era, nor is it related to modern paint; Secondly, from an aesthetic perspective, Cremona's painting process ultimately produces a comprehensive effect of the combination of ossification layer and paint layer; Thirdly, this technique is completely different from the methods used by all subsequent manufacturers; Finally, only through in-depth research on the effect and quality of Cremona paint can the secret of the formula be revealed. Based on the above conclusions, combined with our experience and extensive research, we have come to the conclusion that placing the Cremona piano under summer sunlight will gradually soften the paint, which is due to its low heat resistance. If a damp cloth is used to wipe the surface, amber color will remain on the cloth. Sometimes it may even have a very red color tone, but this is not the true color of paint. The paint on the parts that come into contact with the hands is worn out, causing the color to become lighter and the tone to change. When the middle of the piano backboard touches a rough surface, some very small particles like powder will fall off. If the damaged area continues to be worn, the area will become larger and larger along the pattern of the backboard. In other words, the paint on the backboard will never peel off piece by piece because the paint is strong, only some powder particles will be knocked off. This phenomenon is caused by the brittleness of the paint and the different absorption of ossification fluid by different parts of the soundboard wood. Paint does not mix with the ossification layer, and the degree of damage is determined by the mechanical strength of the bond between the paint and the substrate. In fact, in the lighter colored patterned areas of the soundboard, there are fewer pores that can fix the paint, so the paint is prone to peeling off; On the other hand, the darker colored patterns have the opposite situation, especially in the areas where the wood grain is cut, where more air holes result in a stronger bond.

The paint fragments under the microscope have very thin edges, sharp like glass shards. But if we continue to observe, especially in summer, a few days later, the edges of the fragments become soft and dull, indicating that the paint at that time, especially the middle of the backboard, was not as hard or poor as modern alcohol paint or lacquer. On the contrary, paint has a very good impact on the sound of the piano. Some people speculate that Stradivari had already adopted this technology back then. It is worth noting that people who are ignorant of qin making often prefer Stradivarius guitars with polished back lacquer, rather than guqin with well preserved paint film. Sometimes exceptions occur when a large piece of paint falls off the piano, and the coating inside initially appears opaque, but gradually becomes shiny and transparent after a period of use. This indicates that the paint has adhesion to the ossification layer and has the ability to make it transparent and shiny, while the ossification layer is insoluble and unchangeable.