Is 1/10 carat of diamonds noticeable?

Barely, at arm's length. The 1/10 carat is split across the oval links, so each stone is very small and reads as a faint sparkle rather than a focal point.

Is 10k gold good for a necklace?

It is durable and holds up to daily wear, but it is 41.7% gold, so it looks paler than 14k or 18k. That trade-off is normal at this price.

Will a 17-inch chain fit?

17 inches sits at the base of the neck on most women. It is shorter than the common 18-inch length, so check against a chain you already own if you like a looser fit.

What comes in the box?

The necklace in boxed packaging, per the listing. No pouch, polishing cloth or extra chain is mentioned.

Is $512 a fair price?

With only one new price listed, there is nothing to compare it to. Weigh it against the 1/10 carat total and 10k gold content rather than a discount claim.

Can it be worn in water?

10k gold resists tarnish, but repeated exposure to chlorine and soap dulls the polish and can loosen the spring-ring clasp. Take it off for showers and pools.