DITTO SOB - very fine sand will be a detrement rather than an enhancement to your soil. When I encountered clay soil while landscaping I used a combination of compost and mason sand. River sand, washed river sand and play sand were all to fine. Do a test and rub different types of sand between your fingers. You will feel the difference. Coarse is better.
Even in non-clay soil fine sand will turn to clay. Not good.