1918.] The N.Z. Journal of Science and Technology. 
37 
Sand. —Used extensively as a constructional material in the making of 
asphalt paths, and as an ingredient of concrete, mortar, and sand-lime 
brick; used also for filtering purposes, for foundry moulds, for sand¬ 
blast, &c. Pure quartz-sand is one of the principal ingredients of 
glass, and has most of the uses of quartz (which see). It is used also 
in the manufacture of carborundum and silico-titanium. Calcareous 
sand may be used as a soil-dressing, and if sufficiently pure, as is coral- 
sand and some shell-sand, for various other purposes. (See Limestone). 
Sandstone. —Used as building-stone, for grindstones, sharpening-stones. 
Scheelite. —Tungsten-ore. 
Selenium .—Some selenium is obtained at Waihi during the refining of gold- 
silver bullion. Selenium is used for manufacture of red glass and red 
enamelled ware, and for selenium cells. 
Serpentine. —Pock used for ornamental purposes. May become a source 
of magnesium. 
Shale. —-Used for bricks, tiles, cement. See also Clay, Slate. 
Shells, Sea.—Used for making lime and cement ; useful also for poultry. 
Sinter, Calcareous.—May be used as a soil-dressing, for manufacture of 
lime, &c. See also Limestone. 
Sinter, Siliceous.—May be used for making sodium silicate (soluble glass), 
and has many other possible uses. See also Quartz. 
Slate. —-Used as roofing-material, &c., and (if ground) in the manufacture 
of paint, roofing-paper, and artificial stone ; may also be used for heat- 
insulation. Rocks similar in composition'—such as shale, argillite, 
and claystone—have the same uses as ground slate. 
Soapstone (or Steatite).—Used in making laundry-tubs, bath-tubs, sinks, 
switchboards, acid-tanks, fire-backs for stoves, hearthstones, door-sills, 
and in artificial flooring. “ Soapstone ” may be regarded as a trade 
name for somewhat impure talc, capable of being fashioned into the 
articles mentioned. See also Talc. 
Sulphide Minerals. —Source of sulphur for sulphuric acid. See especially 
Pvrite. 
Sulphur. —-Used as a fumigator and insecticide, and in the manufacture of 
sulphuric acid and numerous other chemical substances; is one of the 
ingredients of gunpowder, and of vulcanized rubber; in certain cases is 
a valuable soil-dressing. 
Talc. —-Used in the paper, paint, and soap trades, chiefly as a filler ; in 
the manufacture of roofing-paper, lubricating-compounds, toilet powders, 
“ French chalk,” motor-car-tire powder, rubber, gas-tips, and crayons 
(see also Steatite) ; in sizing and bleaching cloth ; in the tanning and 
ropemaking industries ; in insulating steam boilers and pipes, as an 
electric insulator, and as a foundry facing. Has also been used in the 
manufacture of porcelain. “ Talc ” is here used as a trade name which 
seems to include the purer varieties of the mineral talc, and also ground 
“ soapstone ” or “ steatite,” as well as ground “ talc.” 
Tin-ore. —The source of the metal tin, and of various chemical substances 
' used in the arts and manufactures. 
Titaniferous Ironsand. —May be used in the manufacture of iron and steel, 
and, if high in titanium, for ferro-titanium. See also Umenite. 
Tungsten-ore. —Tungsten is required for the manufacture of tungsten-steel, 
used especially for tool-steel, and in the manufacture of filaments for 
electric lamps. Its compounds are used in the preparation of some 
colours and enamels. Tungstate of soda is used as a mordant and for 
fireproofing cloth fabrics. See also Scheelite, Wolfram. 
