Based in the center of Germany’s Jura limestone region, Vereinigte Marmorwerke (V.M.) Kaldorf GmbH was founded in 1971 as a supplier of local stone materials. Today, the company - whose name means “United Stoneworks” in English - operates multiple quarries and stoneworking facilities, and it supplies Jura limestone to markets around the world.
V.M. Kaldorf is located in the village of Kaldorf - part of the city of Titting - an area plentiful in Jura limestone resources. The company has a total of five quarry sites in the region, three of which are active. V.M. Kaldorf has a total of 130 employees, including 17 in the quarries and 14 in the sales/administration office. The remainder of the company’s employees work in production.
Quarrying operationsThe Jura limestone quarries in the region have multiple layers, and they contain a number of different stone varieties. Typically, the type of material that is yielded depends on which layer is being worked. Layers 1 through 7 yield gray-blue varieties; layers 8 through 16 are light beige and well-suited for products such as tiles and stairways; and layers 17 through 25 are dark beige and well-suited for elements such as facades and monuments.
The breakdown of materials among the different layers is similar from quarry to quarry, explained Lorenz Branner, who directs quarry operations at V.M. Kaldorf. Of the three quarries currently in operation by V.M. Kaldorf, the company is working different levels in each quarry. Working multiple levels ensures that V.M. Kaldorf will have steady production and inventory of all materials. Blocks have a typical size of 1.3 x 2.5 x 1.5 meters, but the company is able to produce blocks as large as 3 meters in size. The thickness of the block is based on the natural characteristics of the quarry, and this can change depending on the layer. Block production is carefully organized according to the quarry layer, and the blocks are never mixed. Armed with cans of spray paint, Branner and others quickly identify blocks as they are produced.
As quarrying within a quarry site progresses, experience is an important factor in determining where to move. “You develop a sense of where you need to go,” Branner said. “It is always important to study the quarry walls and determine where to go. We prefer a wider quarry, where there is room to operate.”
V.M. Kaldorf excavates approximately 20,000 cubic meters of material per year, and it only digs out what is needed for construction. In all, the company covers approximately 6,000 to 7,000 square meters of quarry area per year, and after quarrying operations are completed, the land is “reclaimed.” The quarry site is filled with waste and clay, followed by soil to encourage plant life to grow.
ProductionV.M. Kaldorf has several stoneworking facilities in place, and all are located near the quarry sites.
Blocks are processed on a variety of sawing equipment, depending on the finished product. These include gangsaws and a Bidesimpianti diamond wire saw for slab production. The slabs are then processed on slab polishing lines from Simec of Italy.
In the cut-to-size area, equipment includes bridge saws from Löffler of Germany and an automated edging machine, as well as a range of hand tools.
Water treatment is a priority in V.M. Kaldorf’s production, and the company has a system in place to separate the slurry from the wastewater. The slurry is then carted away, while the water is reused in the factories.
In all areas of production, quality-control is a key element of the process, and materials are carefully inspected before being packaged for shipment.
Approximately 50% of the stone sold by V.M. Kaldorf is tile and slab production; 40% is cut-to-size work such as interior and exterior facades, custom-produced tiles and countertops; and 10% is blocks and landscape materials.
Sales and marketingA total of 70% of V.M. Kaldorf’s production is sold within Germany, and 30% is exported. Hungary is a key export market for the company, and China is strong for block sales. In the U.S., the company sells through representatives such as TriStone & Tile, Inc. of Nuys, CA, and Facings of America in Phoenix, AZ.
According to Hubert Kuenzl, who works in the company’s commercial department, sales have been steadily improving over the course of 2009.