Apparenty you bought ground Dolomitic limestone. It is difficult to
feed accurately through a lawn spreader. You may try a more wide open
setting on your rotary spreader. If that does not work you may try
broadcasting. I don't know where you live, most soils in the east
except the natural limestones soils will be acidic. A soil test is
always reccommended. But limestone/ or dolomitic limestone is neutral,
so the danger of making your soil basic is not a problem. Dolomite is
Calcium Magnesium carbonate, a good source of magnesium if you need,
but slower to react with acid in the soil than calcium carbonate
(Limestone)