• Spread a thin layer of mineral oil on the surface of the metal mold before pouring liquid paraffin to allow easy release of the paraffinn block
• may use a plate that has both heated(<60C) and cool spots so that you can slide the paraffin mold between the spots when heatitng or cooling needed
• cover the sample completely with paraffin--at least 3-5mm above the top of the sample

• arrange the sample to the desired orientation while the paraffin is still molten; if upright orienttation of a sample is desired, first solidify paraffin bottom on a cool surface with the upper paraffin still being liquid, thenn use the solidified bottom as a "sticky ground" for making the sample upright
• when the paraffin block is solid, it can be stored as a cool place (4°C-RT)
• paraffin can be easily dissolved by solvents such as xylene; this makes possible the staining of the sample with different types of stains.

• melting temperature is 35°C--softer than paraffin
• dissolved in EtOH---does not need intermediate solvent
• preferred method for immunolocalization-- low melting temperature that is less likely to destroy antigenicity
• disadvantages of steedmans wax: maybe too soft for hard tissues; storage and sectioning need to be done in temperature-well controlled environment; more expensive than paraffin

solidify (polymerize) when an "initiator" is added and under the appropriate conditions such as heating, having a catalyst, or under UV irradiation, or a combination of these. 

polymerization of plastic media is inhibited by oxygen--use a parafilm barrier to block oxygen or use an alternate method