Quartz sand is a wide-spread mineral in Latvia. The chemical compositions and particle size distribution of Latvian minefields Bale (Devonian period) and Skudra (Jurassic period) were observed. Latvian quartz sands were compared with sands from other mines of the region. Latvian sand usability for glass industry was specified after corresponding treatment. The necessity of Latvian quartz sand enrichment for improving of chemical composition and particle size distribution was demonstrated. Main methods of quartz sand enrichment and the requirements for sand treatment factories were described. Also, the nearest sand mines, enrichment factories and main glass production lines were observed. Mainly, Latvia has alluvion period quartz sand, but it lies at large burial depth and it also has high content of coloring oxides (iron and titanium), these factors limit the usability. The main requirements for sand foreseen for building and metal industries are particle size and its distribution; chemical composition is not so important, therefore, mainly, Latvian quartz sand mines with SiO2<98% are useful for building industry. Thus, for such purpose this sand must be only separated by fraction and, in some cases, e.g. for dry mixture, also drying and milling. Glass and ceramic industries have much stronger requirements regarding chemical composition and particle sizes, therefore, different treatment and enrichment methods must be used for obtaining corresponding products. It is defined that the most perspective for glass industry quartz sand minefields in Latvia are Devonian period sands in Vidzeme and Jurassic sands in Kurzeme, but complex treatment is needed.