Chalk is made up of calcium   carbonate .We teachers use chalk to write on board every class and are exposed to it for longer time. So thought of exploring the microscopic view of chalk dust settled on class room floor during traditional teaching with dusting under the foldscope.

Chalk dust is considered to be non toxic but if over exposed ,may cause respiratory problems due to its accumulation .Chalk dust is allergic to some people .

Chalk dust appeared black under the folsscope even though it was white in colour.

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