In color theory, a purple is defined as any non-spectral color between violet and red (excluding violet and red themselves). The spectral colors violet and indigo are not purples according to color theory but they are purples according to common English usage since they are between red and blue.
Dry ice fog is a thick, dense, low-lying fog created exactly the way fog in nature is. created, by condensing water vapor out of the atmosphere. We use dry ice (the. solid form of carbon dioxide) to condense the water vapor out of the air. Dry ice. fog contains no chemicals, glycols, or oils, and is truly a water based fog.
Dry ice, sometimes referred to as  cardice  (chiefly British chemists), is the solid form of carbon dioxide. It is used primarily as a cooling agent. Its advantages include lower temperature than that of water ice and not leaving any residue (other than incidental frost from moisture in the atmosphere).