Talking at work isn't too much of an issue where I work. I'm in a team with six other people and it is nice to sit back and chat, constant head down looking at a spreadsheet gets a little tedious after a while and so it is a welcome break from that. I don't mind once the whole team are in for those that are on an early shift to go and get breakfast and bring it back to the desk as they're entitled to a break, just if they were to spill baked beans across a keyboard for example they would have to pay for it, this wouldn't be ideal if at for example 9:00am everyone left their desk as it would look terrible.
I have had to take a couple of the team to one side before to discuss their productivity which is reduced by constant chatting, along with other issues such as absence, or generally not doing the work they should do. Chatting is something that I have questioned why so much, is it not enough work for them as it is impacting the rest of the team and so sharing of a workload could help with this, also this could be down to where they are sat, is it difficult to concentrate and would they prefer to be moved. Absence I have questioned if there is too much work for them causing stress or other issues, and how it could be resolved, someone was moved as where they were was causing migraines, moving them helped. Lack of productivity, is this because they don't understand their job role and if it is a training issue. So all these issues could be looked at and could cause too much chatting as they simply don't like their job and therefore they chat.
These are only in extreme cases, where it is an insignificant issue this is usually brought up in a six monthly one-to-one which gives them an opportunity to make suggestions, raise concerns including those with others in the team in a confidential aspect, giving them the opportunity to look at what they would like to achieve in the next year within the business, giving them an opportunity to progress.
Cliche I know, but it does work and to summarise, talking is fine as long as it isn't excessive as it could impact productivity not just for themselves, but also throughout the rest of the team.