When people talk about a bag, they talk about its size, its colour and its shape. The small metal parts get less attention, and they are the part your eye meets right next to your hand, your wrist and your jewellery. Zips, clasps, rings, studs and chain links are a bag's own jewellery, and they either agree with the metal you are wearing or argue with it.

Three finishes, three moods

Bag makers call all of these metal parts hardware. Three finishes cover almost every bag you will see. "Gold-tone" and "silver-tone" describe the colour you see, not what the metal is made of, so check the label if it matters to you.

• Gold-tone is warm and yellow. It looks dressy and classic, and it sits naturally with brown, tan, cream, olive and navy.
• Silver-tone is cool and bright. It looks crisp and a little modern, and it works well with black, grey, white and blue.
• Matte or dark covers black, gunmetal, brushed and antique finishes. The metal stops shining, so it reads as a detail instead of an accent.

Match, mix or mute

Before you choose, look at the metal you already wear in plain sight: a watch, earrings, rings, a belt buckle, glasses frames, shoe buckles. That is the metal your bag will be compared with. You then have three options:

• Match the bag's hardware to your other metal. It is the tidiest look, and the least likely to go wrong.
• Mix on purpose, with both gold and silver in the outfit.
• Mute the hardware with a matte finish, so the bag stays out of the argument.

Pick a hardware finish and the metal you are wearing below, and read what the pairing does.

How to mix without it looking like an accident

Mixing gold and silver is common, and it works when it looks planned. Three habits make it look that way:

• Repeat each metal. One gold thing alone looks like a mistake. Two gold things and two silver things look like a decision.
• Let one metal lead. Roughly two parts of one to one part of the other is a good balance.
• Use a bridge. A two-tone watch or a belt buckle that carries both finishes links the bag to your jewellery.

Count the metals you are wearing first, then decide whether the bag should repeat one, add the other, or stay quiet.

When to break the rule

None of this is strict. A bag's colour can outweigh its hardware: a cream or tan bag usually looks right with gold, and a black or grey one with silver, whatever you wear on your wrists. A bag with a large metal logo plate is a different case, because then the hardware is branding and not an accent, and it will stand out whichever finish you pick. If you carry your bag across the body and your jewellery is mostly out of sight under layers, you can simply choose the finish you like best.

What to look for

• One finish throughout. The clasp, zip pulls, rings and feet should all be the same tone. Two slightly different golds on one bag look careless.
• Plain, small hardware. Simple shapes and no large logo plates make a bag easy to pair at any price.
• A finish that suits your other metals. Check the watch, earrings and buckles you wear most before you choose between gold-tone and silver-tone.
• Matte if you are unsure. Dark or brushed hardware goes with both metals and is the lowest-risk choice.

You can try all of this with a bag you already own. If you want a different finish, second-hand is a good place to look, and replacing a single strap or chain can change the metal on a bag you already like.