Since 1998, WOLFF & MÜLLER Quarzwerke GmbH has been continuously certified according to DIN EN ISO 9001 by BÜV NO.
Our standards are high. We strive to increase and improve functionality on an ongoing basis in order to produce and transport high-quality minerals to customers around the world. We monitor and document all phases of our production, from extraction to completion of final products. The quality of our products is based on the existing excellent raw materials and a powerful, modern, quality-assured process technology, as well as our in-house quality management.
Based on these quality assurances and our experience, WOLFF & MÜLLER Quarzwerke GmbH produces standard products as well as customized products.
The standard processes are mainly automated. Continuous improvement and optimization of our production technologies and the expansion of our natural resources are the basis for our quality products and the basis for the top products of our customers.
The highest demands are placed on the quality of our silica sand. It has a monocrystalline structure, is rounded edged and is of light and uniform color and is available in different grain sizes.
Our silica sand and quartz gravel are produced and monitored by factory standards. Filter sands and gravels are subject to monitoring under the requirements of DIN EN 12904 and DIN 4924.
The fine and coarse aggregates from our gravel plants are produced and monitored in accordance with the requirements of DIN EN 12620.
As of 2014, all measures have been taken in order to certify WOLFF & MÜLLER Quarzwerke GmbH according to DIN EN ISO 50001 Energy Management System (EnMS).