Brincos de tachas

Studs are measured in millimetres across the front, and the numbers read smaller in real life than in a photograph.

Three to four millimetres is a discreet everyday stud; five to six is clearly visible at conversational distance; eight and above is a deliberate statement.

Mark the stated figure on a ruler and hold it against your ear - it takes seconds and is far more reliable than judging from an image.

A screw back has a threaded post, and the back winds onto it rather than gripping by friction, so it cannot simply work loose.

It is the sensible choice for earrings worn continuously and for children, and it is the single most effective way to stop losing studs.

The trade-off is time: screw backs take longer to put on and take off than a friction back does.

Almost always the back. A friction back grips the post by tension, and that tension gradually relaxes with handling until the back no longer holds.

Replacing friction backs with locking or screw backs is inexpensive and solves it permanently.

It is also worth checking the post for a groove - some posts are notched to hold a locking back, and a plain back on a notched post will not grip properly.

Studs are the one earring style that really permits it, and many people do.

What makes a design suitable is a low profile, a smooth outline without sharp points, and a back that will not work loose against a pillow. Flat-backed fittings are the most comfortable for this.

Anything with a raised setting or a pointed stone is better taken out at night, and any new piercing should follow whatever aftercare advice it came with.

Smaller ones. The usual approach is graduated - the largest stud in the first hole and progressively smaller ones above it, which reads as deliberate rather than accidental.

Studs work far better than hoops or drops in a second or third piercing, because several small pieces can sit close together without tangling.

Mixing metals across a set of piercings is entirely conventional, and a two-tone piece somewhere in the group ties a mixed set together.

Yes - a pair is assembled from stones chosen to agree with one another, which is a different exercise from selecting a single centre stone for a ring.

Size, colour and cut all need to agree - a stone slightly larger or warmer than its partner reads immediately.

If one of a pair is ever lost, replacing it to match is harder than buying the pair was. Each listing names what is set, which is the information a jeweller would need.

A halo stud rings a centre stone with smaller stones set close around it, with very little metal showing between them.

The eye reads the whole cluster as one bright object rather than a stone with a border, so a halo stud presents considerably larger than its centre stone alone.

It is the most efficient way to get visual scale on a lobe, which is why halos are so common in stud designs.

Small, light studs with a screw back are the usual choice, and screw backs exist largely for this reason.

Scale matters more than anything: a small stud sits flat and catches on nothing, which is exactly what a child needs.

Any advice about a new piercing itself is a matter for whoever performed it rather than for a jeweller.

Studs are the least likely earring to, because they are small and light and the load on the piercing is minimal.

Stretching over years is associated with consistently heavy earrings - large hoops and long drops - rather than with studs.

If you wear heavier pieces regularly, alternating them with light studs gives the lobe a rest.

The back of the setting and the length of the post matter more than the visible front, because that is where residue collects out of sight.

Studs need it more often than other pieces, because they sit against skin behind the ear and are frequently left in for weeks at a time.

Sequence helps as much as method: put studs in after hairspray and perfume rather than before, and take them out before anything that involves chlorinated water.