For a condolence note or longer prose, you need a letter sheet.

Letter sheets lend themselves to airmail usage because they are lightweight.

It is extravagant grandiloquence confined to a newspaper about the size of a double letter sheet.

The embossed paper of a letter sheet or stamped envelope is called an indicium.

The popularity of folded letters led postal authorities to introduce stamped letter sheets.

Prepaid letter sheets, with a design by William Mulready, were distributed in early 1840.

He flipped through his closely lettered sheets.

This is known as Mulready stationery, after the man who designed the pre-paid envelopes and letter sheets.

Known as air letter sheets, they took up much less space then regular letters, and by August the use of these sheets was extended to civilians.

They have established a database in which the earliest postmarks on stamped envelopes of postal card or letter sheets is kept.

The US has not produced any since, other than air letter sheets or aerograms which became available in 1947 and were likewise discontinued in 2006.

This mail is usually a letter sheet because the use of envelopes was not popularised until after the introduction of postage stamps.

Other innovations were the introduction of pre-paid William Mulready designed postal stationery letter sheets and envelopes.

It can be an issue of a military force where an army, perhaps in a distant war, issues letter sheets for the use of its troops to write home.

The first piece is a letter sheet with an embossed 25-centesimo Cavallino, or "little horse," a forerunner of stamps in the kingdoms that became Italy.

In philatelic terminology a Letter sheet, often written lettersheet, is an item of postal stationery issued by a postal authority.

The rarest item is a letter sheet bearing two 1-penny stamps issued in 1847 on the island of Mauritius, in the Indian Ocean.

These became available in the U.S. in 1861, but the first official postal stationery were the 1838 embossed letter sheets of New South Wales.

Much later, 1947 in the U.S., letter sheets morphed into lithographed air letter sheets or aerograms.

The first items of postal stationery to be issued for the Sudan were postcards, post paid envelopes and letter sheets in 1887 and newspaper wrappers in 1898.

A piece of 'postal stationery' is a stationery item, such as an envelope, letter sheet, post card, lettercard, Aerogram or newspaper wrapper, with an imprinted stamp.

First Day of Issue, 6 May 1840, Mulready letter sheet Royal Insight (British Monarchy website)

He is best known for his romanticizing depictions of rural scenes, and for creating Mulready stationery letter sheets, issued at the same time as the Penny Black postage stamp.

The National Postal Museum's exhibition shows stamps on "covers": folded letter sheets (similar to today's air mail stationery, where the address is on the outside flap) or the more rare envelopes.

In philately a cut-out is an imprinted stamp cut from an item of postal stationery such as a postcard, letter sheet, aerogramme or wrapper and used as a normal stamp.