In Zhejiang Quzhou, if the social security base is 6300, the individual's deduction amount is calculated based on different insurance types and their respective contribution ratios. The approximate total deduction for an individual is around 693 yuan per month. Here's a breakdown by insurance category:

1. Pension Insurance: The individual contribution ratio is 8%. So, for a base of 6300 yuan, the monthly deduction is ​
   ×8%=
   yuan. This part of the contribution goes towards building the individual's pension account for future retirement benefits.

2. Medical Insurance: The individual contribution ratio is 2%. Thus, the monthly deduction is ​
   ×2%=
   yuan. These funds are used to cover medical expenses when the individual needs medical treatment, helping to relieve the financial burden of healthcare.

3. Unemployment Insurance: The individual contribution ratio is 0.5%. So, the monthly deduction is ​
   ×0.5%=31.5
   yuan. This contribution provides a form of income protection in case the individual loses their job involuntarily.

4. Work - related Injury Insurance and Maternity Insurance: For work - related injury insurance and maternity insurance, the individual does not need to contribute. These two types of insurance are fully borne by the employer. The employer's contribution to work - related injury insurance varies according to the industry risk level, and the contribution to maternity insurance also has its own rate, which is used to safeguard employees' rights and interests in case of work - related injuries and during the maternity period.

In conclusion, when the social security base in Quzhou is 6300, the individual's total monthly social security deduction is approximately 693 yuan. This amount is crucial for ensuring that individuals can enjoy various social security benefits in the future.