Top quality: discover knoll stone
Knoll starts with grade double A stone, selecting from only the top 3 to 10% of what is available, depending on the variety. With exacting quality assurance procedures, Knoll-selected purchasers go out to the quarries to evaluate marble before it starts on the journey toward becomming a Knoll top.
Each block of marble, weighing roughly 20 tons, is cemented to a trolley and sent to the factory. Depending on its grade and rarity, the blocks are cut into slabs utilizing either a multiblade or a monoblade process taking up to eight hours.
Once in the yard, the slabs (cut between 2 to 3 centimeters thick depending on the application) are left to acclimatize for about three weeks before the stone is further processed. Producing a unique Knoll marble top is a long process of about 12 weeks in duration.
Each slab is surveyed to ensure the harmony of the resulting top by a highly qualified stone master using templates representing the various shapes and sizes of the required tops. Here the red line is the apprentice’s go, and in black is the master’s revised cut line while optimizing only the highest quality portions of the slab. Knoll adheres to very exacting standards, surveying by eye the veining, pattern, allowable inclusions and other criteria, that together determine not only which marble slabs are selected but also inform the cut.
The shape of the top is created with a series of cuts beginning with a rough cut that is then precisely machined to Knoll edge specifications utilizing computerized, numerically controlled, water cooled, polycrystalline diamond blades and cutters. When applicable, a mesh is applied to the bottom surface of the top to provide additional support.
Skilled craftsmen hand-finish the table edges to further soften any imperfections. Having been saturated with water during the manufacturing process, the pieces are then sent to the drying room so as to allow as much moisture as possible to evaporate before starting the finishing process.
The undersides of the tops are sprayed before being dried again in preparation for Knoll’s signature maintenance-free finish. (The transparent polyester coating-polished or honed to a satin (matte) finish-creates a durable, nonporous surface to prevent use-associated stains.)
The tops are finished over a lengthy and highly skilled process. Depending on the properties of the stone, the slab is coated multiple times to ensure an even and lasting finish. Of course, they are carefully inspected along the way throughout this process.
After several weeks of processing, the tops are finally ready to be shipped to our various locations around the globe. All of the tops are crated, and for safety, pieces larger than 20″ round are crated vertically, with stabilizing wooden slats for the safest transit.