Dear readers,
Please remind me the author and name of a scifi book (I think it was a space opera) in which the earth forces(as far as I remember) were using sand in space as a weapon to stop alien invasion ships. The sand was used as shield/mines in space, so that the alien ships that were going through the sand cloud would perish because of impact with sand particles.

Thank you very much for your help

That would be one of the series by Ian Douglas
Maybe the Legacy Trilogy or Inheritance Trilogy.
Sandcaster rounds were used in battle for Sol