Mica

A soft, translucent solid which may be shipped in sheet, powder or crystal form. Widely used as an insulating material and as a dusting powder for rubber.
Must be protected against damage by salt water, as saline destroys the insulating properties of the mica.
The cases in which mica in any form is packed should be of sound construction and lined with good quality paper. The wood used in these cases should be well-seasoned, dry and free from stains or traces of mildew, as with variations in climatic conditions, cases may develop heavy mildew, inside and out. Some damage to the contents, mostly at the top and bottom inside surfaces, accompanied by decomposition of the paper linings, may result. This mildewed condition is usually found where no air circulation has been possible. Cross battens on the tops and bottoms of the cases are effective in preventing mildew.
Mica waste should be dry at the time of bagging as any moisture rots the bags where they are in contact with each other in stowage, and where air circulation is restricted.
Mica is non-combustible, but loses its natural luster by fire, although it does not char or break. If smoke discolours the surface its commercial value is diminished considerably.
When wet by fresh water and the colour of the packing cases penetrates the contents and stains the mica (which may also be integrated with its wrappers), its potential value may suffer but the unaffected portion may be salved by drying the mica by sun heat or in the open air, although this may be a very costly operation.

MICA SCRAP (In bags)
A mineral like glass that splits easily into sheets. Mica is a soft translucent solid obtained from washing micaceous earth, or grinding rock containing the substance. It is shipped in powder or crystal form and may also be in sheets.
A glass substitute, it is also used in the manufacture of fire-proof paints, asphalt, paper, linoleum and as insulation material. Sulphuric acid is contained in its make up and can cause the packaging (bags) to rot. The decay of the bags may be prevented by providing good ventilation which stowage on pallets assists.
Mica talc or white mica is also known as Muscovite or Siberian glass and often shipped from India.