Canada revenue stamps, unlike postage stamps, are used to collect taxes or fees on various items and to show that these taxes have been paid.These revenue stamps can be found in virtually every household on some old documents. These documents include old cheques, wills, passports, gas inspection certificates, sales contracts, mortgages, hunting licences, stock certificates, war tax documents, jewellery receipts, tobacco products, liquor, drugs, playing cards, shipping documents, money orders, legal papers etc. In the design of these stamps trial color proofs were prepared in very limited quality to determine the most suitable colors for each denomination and design.