A time capsule is a historic cache of goods and/or information, usually intended as a method of communication with future people and to help future archaeologists, anthropologists, and/or historians. Time capsules are sometimes created and buried during celebrations such as a World's Fair, or at other events such as a cornerstone laying for a building.

The latter plays an important role in relation to the 1½ pence coin, as in England in the 19th century was usual placement within the stone of British coins of each denomination in circulation. Rarely, 1½ pence coins were used, but several sites are now known, regardless of geographic location within the British Commonwealth, where it was part of such ceremony which it is described in the next section.

The cornerstone [or foundation stone] concept is derived from the first stone set in the construction of a masonry foundation, important since all other stones will be set in reference to this stone, thus determining the position of the entire structure.

In modern practice, normally, a CEO of the organization, or a local celebrity or community leader, will be invited to conduct the ceremony of figuratively beginning the foundations of the building, with the person's name and official position and the date usually being recorded on the stone. This person is usually asked to place their hand on the stone or otherwise signify its laying.

Often still, and certainly until the 1970s, most ceremonies involved the use of a specially manufactured and engraved trowel that had a formal use in laying mortar under the stone. Similarly, a special hammer was often used to ceremonially tap the stone into place.

The foundation stone often has a cavity into which is placed a time capsule containing newspapers of the day or week of the ceremony plus other artifacts that are typical of the period of the construction was something common or traditional in the daily life in Victorian England, and first years of the 20th century. Coins of the year may also be immured in the cavity or time capsule , which I consider at least somewhat curious, the use of the small 1½ pence, even its purpose was circulating in the colonies.

As a demonstration I posted examples of those, some quite historical indeed, but anyway, is too much information to display on one page, thus I dedicated a sub-page to each. The visitor can browse all landmarks own sub-pages from the interconnection within table, marked LINK.