The Northumbrian rune today is called Stan, which translates to ‘stone’. It is the shape of two Pertho runes put together, or alternatively, an upside-down and rightside-up Ehwaz superimposed on one another. Stan is a native English word, coming from the proto-Germanic *stainaz. However, RI Page states in his An Introduction to English Runes that the Stan rune never appears engraved on a runestone. It is only found in manuscripts, which puts the date of its invention much later, post-conversion. Stan is supposed to represent the sound ‘st’ found in the word stone; it wasn’t exactly a linguistic necessity.

Partly because its name has been in Germanic languages so long, there is lots of material for possible interpretation. A stone is a stone, and many of the things we think of today; its hardness, use as a weapon, use for building, strength and stability, are timeless and would have been ascribed to stones then as well. However, there are also some interesting historical notes that open up more options.
The first is perhaps the most obvious; a majority of our surviving record of runes are engraved onto large rocks called runestones. In this way, Stan could represent recorded knowledge. It could also represent stability and the preservation of knowledge in the face of the march of time. The runestones also represent attaining a certain level of craftmanship. Inscribing a message would be time-consuming and labor-intensive work.

Another option comes to us from the Norse word hörgr, which means an altar site, possibly made of a pile of stones. In the Poetic Edda, Freyja speaks of one of Her worshippers: “He made me a high altar of heaped-up stones: the gathered rocks have grown all bloody” (translation from Andy Orchard). The Old English cognate for this is ‘hearg’, which survives today as the word ‘harrow’. Stan could be associated with holy places and worship of the Gods and other spirits.

I think there’s also an argument to be made for associating Stan with the ‘bones’ of a person or place; the basic structure that holds it up. I make this leap based on the story of the giant Ymir’s dismemberment which created the world. His bones are used to make the mountains and stones, the bones of the earth. Mountains are often associated with Jotuns in the Eddas, wild places that go untamed by the Gods. I might associate this rune with the Skadhi as well, who was known for Her love of the mountains. Skadhi went so far as to leave Her husband Njordh because She missed them.
Stan the Stone, with stone’s wide range of meanings and applications, is a more ambiguous rune than some others. How you choose to interpret this is, as always, up to you! Check out Gar, Calc, and Cweorth for more information on the Northumbrian runes!