Which timber is most common?

Mahogany, by a clear margin, followed by walnut and then oak. Between them they cover the bulk of the archive. Beyond those three, single appearances turn up in burr elm, burr yew, mulberry, amboyna, rosewood, tulipwood, sabicu, fruitwood, yew and briar wood.

Are small bureau bookcases unusual?

No. Narrow examples form a defining sub-type rather than an oddity, and dealers advertise the fact. Thirty-eight titles say small, with others reaching for slim, narrow, neat, undersized and miniature. One title specifies 19 inches wide, another two feet, another 28 inches. Within a given period and timber, those proportions push a piece upward rather than down.

Does a royal name in the title mean it's period?

Not on its own. Titles mix period with style, so George I Style, Queen Anne Style, Queen Anne Revival and Georgian Revival all appear alongside the unqualified versions. The style-labelled pieces are generally dated between 1880 and 1930. The Queen Anne-style burr walnut group, double domes included, mostly falls in the 1900 to 1930 band.

Are these always English?

The form emerged in England, but titles record a wide spread of origins: Dutch, Venetian, Italian, Swedish, Danish, Norwegian, South German, French, Irish and Welsh. Swedish painted examples turn up as a small recurring group. Dutch pieces include bombe lower cases and marquetry decoration.

What periods do they come from?

There are two peaks. One sits in the 18th century and Georgian era, the other in the early 20th, taking in Edwardian, the 1900s, 1910s, 1920s and 1930s. Victorian listings are thin, with a further group filed only as 19th Century or 1800s. The earliest specific years attached to pieces are 1700 and one oak example dated 1727.

How often do they come up for sale?

Around 67 are listed on Sellingantiques in a year, and 161 different dealers have offered one. It's a category most general furniture dealers touch at some point rather than a specialist corner. Almost all are single pieces. A pair of Italian double-dome examples sits at the very top of the range, and pairs are otherwise close to unheard of in the archive.