Most airlines have their own rules and restrictions, which are designed to comply with government regulation, but at the end of the day it is up to the airlines how strict they are above the government set regulations. You can usually see the individual airline guidelines on their individual websites. In addition to this, it will also make a difference depending on what country you are flying from; for example flying from the US will mean the restrictions are far stricter.
I would always advise to use common sense; if the item could be in any way a threat to yourself or others it will definitely not be allowed and if in doubt put the item in your main suitcase to be stored in the luggage compartment. In general most airlines won't have a problem with standard jewelry, in fact you are allowed wear jewelry on board and so if there is a problem with the hand luggage aspect, you could always wear it.
When going through security checks you will likely be asked to remove jewelry and put it in a box, which goes through the scanner; this is mainly so that you don't set of the metal detector as you walk through. The exception to this rule would be excessive or jewelry which may be construed as dangerous in any way. You would not, for example, be allowed to wear a highly spiked gothic dog collar and possible not a skate chain. However, if you are sensible and use common sense you should be fine with most jewelry.
I would always advise to use common sense; if the item could be in any way a threat to yourself or others it will definitely not be allowed and if in doubt put the item in your main suitcase to be stored in the luggage compartment. In general most airlines won't have a problem with standard jewelry, in fact you are allowed wear jewelry on board and so if there is a problem with the hand luggage aspect, you could always wear it.
When going through security checks you will likely be asked to remove jewelry and put it in a box, which goes through the scanner; this is mainly so that you don't set of the metal detector as you walk through. The exception to this rule would be excessive or jewelry which may be construed as dangerous in any way. You would not, for example, be allowed to wear a highly spiked gothic dog collar and possible not a skate chain. However, if you are sensible and use common sense you should be fine with most jewelry.
