Izumi no Kami Fujiwara Kaneshige is the founder of the Kaneshige line, and the published sources place him precisely in the city's early : "the smith who appeared after Yasutsugu and Hankei was Izumi no Kami Kaneshige". By tradition he was an arrowhead smith who moved to and turned to forging swords. His dated record runs from Kan'ei to Meireki, in their words "the earliest date is Kan'ei 2, and the last reaches Meireki". He was long thought to be the same man as Kazusa no Kaneshige, who was said to have changed his title out of deference to his lord Tōdō Izumi no Kami. Signed and age-stated works now show Kazusa no born in Kan'ei 3, and the published sources conclude that "Izumi no Kami and Kazusa no Kaneshige were clearly different men".
His work is almost entirely and : "his works are mostly and , and are not seen". The is that of the Kan'ei and Shōhō years, of ordinary width with clear taper, a retained and a compact , which the published sources call "the transitional shape moving from Keichō to ". The is a , closely forged, at times flowing and standing somewhat, with and .
The published sources state that his temper is "broadly divided into two manners". The first is a base with running linked through it and entering, the deep, thick, and running, the bright. One of this kind opens "with a at the base" before the shallow , on a thick, full-bodied blade. The second is a deep- , often bearing a very shallow , with a bright and clear ; of one such the sources write that its deep , thick and brilliant are "the characteristic of this smith when he took up this kind of work". Some are a pure straight temper, "there are also pure ", on "a with , the bright and clear, an outstanding work". Others carry "a shallow , skilfully tempered", or a with a hint of whose "activity within the is lively", and on one "the is notably deep". The runs straight to a , at times swept at the tip.
His are themselves a point of study. The long signature is cut in a distinctive clerical hand, "the signature is in his own distinctive reisho", and in late work the characters grow smaller and the chisel finer. The file marks bear a tendency that the published sources read as "not quite the decorative of later times, but to be seen as its prototype". A rare of broad, elongated form is called "one of few examples and well made".
His blades are bound to the great cutting testers. Many carry the gold-inlaid of the Yamano family, and the published sources use them to date the work: a cut recorded under the name Kanjūrō shows a blade made "when Kaemon was still called Kanjūrō, a work of up to about Shōhō 2 or 3". He is by long tradition the teacher of Nagasone Kotetsu, and his successor Kazusa no , his son or pupil, carried the linked into the for which that later generation is known.
Fujishiro grades him Jō , and fourteen designated works are on record, all in the tier. Of the finest the published sources write that the work is "a blade in which the temper brims with spirit and conveys power". For a collector a signed of his, often with a Yamano cutting test on the tang, is a realistic if occasional encounter, and a dated piece or a is rare.