To determine which statements regarding the Payment of Wages Act, 1936 are correct, let's analyze each statement one by one:

1. Wages may be paid in current coins.
   According to the Payment of Wages Act, 1936, wages can indeed be paid in current coins, currency notes, or by cheque or by crediting the wages in the bank accounts. Therefore, Statement 1 is correct.
2. Wage period can be fixed for weekly payment.
   The Act allows for the wage period to be fixed on a daily, weekly, fortnightly, or monthly basis. There is no restriction against weekly payments. Thus, Statement 2 is correct.
3. Wages are to be paid before the expiry of the seventh day after the last day of the wage period in establishments employing more than 1000 persons.
   According to the Act, in establishments employing less than 1000 persons, wages must be paid before the expiry of the seventh day after the last day of the wage period. However, for establishments employing more than 1000 persons, wages must be paid before the expiry of the tenth day. Therefore, Statement 3 is incorrect.

Based on the above analysis, Statements 1 and 2 are correct, while Statement 3 is incorrect. Therefore, the correct answer is: 1 and 2 only.