A threshold is a fixing problem before it is a stone problem. It has to be the width of the door plus the frame, it is the one piece of floor that is walked across in a straight line every day, and on an external door it is where water sits. 20 mm is the working thickness, the top is honed or tumbled rather than polished because a polished threshold is a slippery threshold, and the edge is bullnosed or eased so there is no arris to catch a shoe.
A threshold is a fixing problem before it is a stone problem. It has to be the width of the door plus the frame, it is the one piece of floor that is walked across in a straight line every day, and on an external door it is where water sits. 20 mm is the working thickness, the top is honed or tumbled rather than polished because a polished threshold is a slippery threshold, and the edge is bullnosed or eased so there is no arris to catch a shoe.
A band of the stone running across the opening, with the grain set to cross the direction of travel — which is the opposite of what a floor does, and is what makes it read as a threshold rather than as more floor.
Entrances, internal doorways in a stone-floored area, and the transition where a stone floor meets a different material.
This is one of the forms where the figure is not the point, and we say so: a threshold is chosen for how it wears and how it is fixed, and this stone is chosen for the rest of the room.
door threshold · threshold stone · door sill · entrance threshold · marble threshold · transition strip
The specifications on these pages are the published supplier and trade-platform figures for Guizhou Coffee Wood Marble, and the decisions each form carries are our own reading of how this material behaves in that job. We have not run a slip test, an abrasion test or a weathering test on any of them. A floor, a path or an external threshold specified for slip resistance needs the tested wet-DCOF figure for the stone and the finish, which we will supply on request.



Where each photograph was taken is written under it: the quarry yard, the sawing line, the polishing line, or the packing bay.
Send the drawing or spec — we confirm slab allocation, thickness, finish, lead time and FOB pricing from China.