Sidewalk Chalk

Sidewalk Chalk

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Chalk is a material made of rough subsoil for lettering especially on boards. It leaves small particles which cling to the board and can be wiped off easily.

Chalk is originally made of natural chalk, so called calcium carbonate, a fine-grained and soft form of limestone. 

Nowadays sidewalk chalk is produced in Germany, Austria and Scandinavia.

Since real chalk is really expensive, sidewalk chalk is made of calcium sulfate so called gypsum or magnesium oxide. Therefore about 55 percent of chalk sold in Germany consists of gypsum.

 Whether a piece of chalk exists of real chalk or not can be ascertained by the test with an acid (for example, lemon juice or vinegar): Lime decomposes to CO2 and calcium acetate.                                                                                Magnesium oxide and also gypsum don't change due to the                                                                          acids.

To produce colored chalk you only have to add some coloring.

Chalk is a wonderful sign medium for everybody, because it can be used on sidewalks, walls, paper and other media.

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Chalk has an enormous significance in Streetart, because an artist can work more exactly whit a piece of chalk than for example with a spray can. That's why sidewalk chalk is often used for 3D chalk art, which is a 2-dimensional artwork drawn on the street itself that gives you a 3-dimensional optical illusion from a certain perspective. Because of the exactness it can be very breathtaking and realistic. 

Many Street artists make their chalk wet before they start to paint, to make chalk sticks more colorful and more covering.

Another advantage of the chalk-art is, that the painting of walls or grounds with chalk is only a temporary change. That means that at the latest the next rain will wash the chalk-art away. 

So if you want to share your critical opinion with many people, without getting into trouble with the police, you should use chalk to write a statement on the street and make it public.

Chalk artists are for example David Zinn and Kurt Wenner.

The Chalk Art Festival Denver shows which importance this type of Streetart has.

The Denver Chalk Art Festival is a FREE two-day street-painting festival, where more than 200 artists spend many hours one weekend turning the streets of Larimer Square into a museum of chalk art. Artists, sponsors and spectators find it difficult to describe the experience that the Denver Chalk Art Festival creates, with live music, featured artists and also youth challenges. 
Next year it is scheduled for the 6^th and 7^th of June.

JJJ