Comparing copper bottles: what actually matters

In a photo they all look the same

A hammered copper bottle is a hammered copper bottle, or so it seems in a list of search results. The differences sit in places a product photo never shows: inside, at the seam and at the closure. Here they are, one by one.

In short

• The inside is the point that matters most: bare copper or a lacquer.
• A soldered seam is not a flaw, but it has to sit cleanly.
• Wall thickness shows up in the weight and in the dents after a year.
• The closure decides whether the bottle can go in a bag.
• A price under twenty euros almost always means a coating inside.

The inside

The one point everything hangs on. In an uncoated bottle the water touches the copper, which is the whole point of the tradition. In a lacquered bottle a transparent layer sits in between; the bottle stays shiny inside, but it does none of what you bought it for.

You can check with a torch. Uncoated copper darkens and goes patchy inside over time; a lacquered bottle stays evenly bright. The price gives it away too: under twenty euros, a coating is close to certain. Why water from an uncoated bottle tastes different is covered in advantages and drawbacks.

The seam

Most copper bottles are a rolled sheet with a soldered seam running along the length. That is normal and not a lesser way of building one. What to look at is whether the seam runs straight, whether no solder has squeezed out, and whether it does not feel like a ridge on the inside.

Seamless bottles made from one piece exist, cost more and are usually heavier. There is no difference in the result as long as the seam is clean.

Wall thickness

Rarely listed in the specifications, but you notice it immediately. Pick the empty bottle up: a thin-walled one feels almost like foil and dents on its first fall. A thicker wall weighs more, survives life in a backpack and stays straight for years.

With our 900 millilitre copper bottle that is why it is heavier than the cheap versions. That is not a drawback; that is the wall.

The closure

This is where the bottle for home parts company with the bottle for the road. A screw cap with a sealing ring holds tight when the bottle lies in a bag. A stopper that merely rests on top does not, and is meant for a bedside table.

Check too whether the closure is bare copper on the inside or plastic. Both work, but it says something about the care taken over the rest of the bottle.

Size

Nine hundred millilitres is the usual size for a day; smaller is easier to carry, larger is more convenient at home. Which size suits your day is covered at length in which size copper bottle. For the table a carafe often makes more sense than a second bottle.

Smooth or hammered

Purely a matter of looks, with one practical side effect: a hammered surface shows fingerprints and small dents less. What that means for upkeep is in smooth or hammered.

What does not count

A certificate on the packaging says nothing unless it also says what it refers to. The same goes for claims like "100% pure", which are about the material and not about whether there is a lacquer inside. And a cleaning sponge in the box is no substitute for a polish; which products work is in cleaning copper.

Have a look at the full range if you want to put these points side by side.