The field consists of one tincture (metals: Or, Argent; colors: Gules, Azure, Vert, Sable, Purpure, other non-heraldic colors; furs: Ermine and variants [erminoys], Vair and variants [vairy], vair bellies, other furs like scaly, papellony, plumetty, honeycomb etc).
The arms with a (main) field of multiple tinctures will not be composed (divided), if
no one of the partitions contains any other charge(s) (device, armorial bearing), or
the charge(s) being placed above all (or the most) of the partitions, with no counterchanged attribute.
The arms will not be composed (divided), if
in the field there is a chief or a base, even if they are loaded with other armorial bearings (they are ordinaries, not fields); or
the field of one tincture being not divided by a line of partition, but some ordinary (or common charge), regardless, if the fields contain some other charges as well; or
the line of partition of a field of multiple tinctures (mostly) being covered by an ordinary (or a common charge), but no other charges (devices, armorial bearings) to be found in any of the partitions (fields); or
the field being fully covered by partitions, like barry, bendy, impaled, chequy, lozengy, (these are fields, basements, partitions of multiple tinctures, not single fields); or
if in the shield there is a stylized natural scene (a ship on the sea, a stream is running down the hill, for example), the arms will be undivided as well.
The (main) field of multile tinctures contains a counterchanged charge (device, armorial bearing).
In the field of multiple tinctures the charge (devise, armorial bearing) was present only in one, or at least in one of the partitions.
The arms was divided, if
the chief or the base logically plays a role of a distinc field (they are covered by the same tincture as the other parts of the field or escutcheon, or [in divided arms] they are loaded by other charges); or
a field or escutcheon of one tincture being divided by a line of partition, even when the fieds contain no other charges (devices, armorial bearings).
The arms was divided, if
in the field of one tincture the line of partition being covered by an ordinary (or common charge), but the position of other charges indicates a divided arms; or
in the field of multiple tinctures the line of partition being covered by an ordinary (or common charge), but one or more of the fields are containing some other devices (charges, armorial bearings) as well.
All coat of arms with some inescutheons, smaller escutcheons (loaded with charges, devices), in any possible position, being counted as divided.
All composed arms counted as divided, like the arms of alliance (assembled from the coat of arms of the spouses), for example.