Every stoneware page on this site says the same thing in the specification panel: variation between pieces is expected. It is worth explaining what that means in practice, because “handmade, so slight variations occur” is the vaguest sentence in retail and it tells you nothing about what will turn up in the box.
What a reactive glaze is
A glaze is a layer of glass melted onto a clay body. A reactive glaze contains something, usually iron and sometimes manganese or titanium, that does not simply melt into a flat colour. It moves, separates or crystallises as the kiln cools. The clay underneath contributes as well, because iron in the body migrates up into the glaze at temperature.
So the finished surface depends on how thickly the glaze went on, where the piece stood in the kiln, and how fast that part of the kiln cooled. None of those three things are identical from one piece to the next, and a kiln that produced identical results would be a kiln running a very dull glaze.
What actually varies
Three things, roughly in order of how visible they are.
Tone. The overall colour shifts. On a mid-brown glaze the range across one firing might run from a warm sand to a deep coffee. It is a shift along one colour, not a different colour.
Break. Where the glaze runs thin, over a rim, along a rib, at the edge of a handle, the clay shows through and the colour goes lighter. How far down the rim it breaks varies by a few millimetres.
Pooling. Where the glaze runs thick, usually the inside base of a bowl or the well of a plate, it goes darker and glossier. In a bowl this is the most obvious difference between any two pieces.
What does not vary in any way that matters: dimensions, capacity and weight. Those are held to the tolerances published in the specification panel, because a plate that will not fit a dishwasher rack is a defect and a plate that is a shade darker is not.
How to order for it
If you want four pieces that sit closely together on a table, buy the four in one order. Stock is picked in the order it was fired, so four bowls bought together almost always come from one firing and read as a group. Four bowls bought over eighteen months are four bowls from four firings, and they read as a collection rather than a set.
If you like the collected look, do the opposite deliberately. Buy two now and two next year. A table where no two plates match exactly is a specific and quite good look, but it only works if you chose it rather than ended up with it.
When variation is a fault
A chip, a crack, a glaze flaw that is sharp under a finger, or a piece that rocks on a flat table: all faults, all covered. A piece that is darker than the photograph is not a fault. Product photographs on this site show one representative example and the specification panel says so on every page.
The practical test is whether the difference affects use. A darker well does not. A rim that breaks two millimetres lower does not. A foot ring that has not been sanded flat does, and we would rather you sent that one back.