![THE CHALK. WHAT IS CHALK? Chalk is a form of limestone that is distinguished by its relative purity and close, fine grain. Humans have been using it for. - ppt download THE CHALK. WHAT IS CHALK? Chalk is a form of limestone that is distinguished by its relative purity and close, fine grain. Humans have been using it for. - ppt download](https://images.slideplayer.com/27/9147361/slides/slide_3.jpg)
THE CHALK. WHAT IS CHALK? Chalk is a form of limestone that is distinguished by its relative purity and close, fine grain. Humans have been using it for. - ppt download
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Trace Elemental Characterization of Chalk Dust and Their Associated Health Risk Assessment | Request PDF
![Trace Elemental Characterization of Chalk Dust and Their Associated Health Risk Assessment | Request PDF Trace Elemental Characterization of Chalk Dust and Their Associated Health Risk Assessment | Request PDF](https://www.researchgate.net/publication/303891825/figure/fig1/AS:941931362271233@1601585345413/Comparison-of-the-trace-elements-averages-of-settled-and-suspended-chalk-dust-samples_Q320.jpg)