The invention provides a method for manipulating or formulating a solid substance which melts under pressure of a gas without degrading at a temperature lower than the melting point of the substance at atmospheric pressure including: applying to the substance a liquefied gas or dense gas to melt the substance without degrading the substance; then contacting the molten substance with a carrier fluid, which is at substantially the same pressure as the liquefied gas or dense gas, to form a solution or mixture of at least a part of the molten substance and the carrier fluid; and passing the solution or mixture into a vessel of lower pressure than the pressure of the liquefied gas or dense gas and carrier fluid to form particles of the substance; and particles formed by the method.