Lime Sulfur, also known as Calcium Polysulfide or Sulfurated Lime Solution, is a molecule made up of multiple Sulfur atoms and a Calcium atom. Lime sulfur generally exists in a dissolved/liquid state. Sulfur powder by itself is not very soluble or bioavailable. Many of our formulations use soluble form of Sulfur (Lime Sulfur) to make it easy for skin to absorb and address the underlying causes of skin issues.