Two Hammers of Thor?

The Eddas state that Thor`s hammer Mjollnir was made by the smith dwarves Sindri and Brokkr and is the subject of many giant slaying myths. It had special properties, being able to produce thunder and lightning and when it is thrown it returns to the hand of the thrower. It was also used as a means of consecration at funerals and weddings, thus alluding to Thor`s joint role as God of war and as a fertility deity. In order to handle Mjollnir Thor needs special iron gloves.
It is of great antiquity and features in Bronze Age rock carvings.
In the Viking Age it became the most important symbol for Scandinavian heathendom in its opposition to the alien religion of Christianity and was worn by adherents of the old faith as an amulet. Today those of us who have heard the call of the blood, the call of the ancient Germanic Gods wear this symbol as a visible expression of our faith in our ancestral Gods.
The etymology of Mjollnir is traced to the Proto Norse *melluniaR
Rudolf Simek in his Dictionary of Northern Mythology specuates that "it may be related to Old Slavic mlunuji, Russian molnija, `lightning`[either borrowed from there or else from an early stage] which would allow an interpretation of `the one who makes lightning; another attempt to explain it, however, relates Mjollnir to ON mjoll `new snow`, Icelandic mjalli `white colour`, and as such would mean `the shining lightning weapon`. In earlier scholarship Mjollnir had been connected with Gothic malwjan and ON mala `to grind` and interpreted as `the grinder`".
The etymology is also discussed in Jaan Puhvel`s Comparative Mythology and Puhvel cites the Welsh cognate mellt and also adds: "It is thus the bolt, and it can be represented also as an[originally stone] ax, a club, or as a counterclockwise hooked cross symbolizing a thunderball, resembling the Indic svastika-`good luck sign`[from Vedic su-asti- `well being, good fortune`]. It was a tool that the god used to `hallow` [vigja] beings in a positive vein[consecrate a bride, revive his own goat team, sactify the dead;cf. Indra`s vajra-cognate with Latin vegeo `arouse, quicken`]."
He goes on to add that both Thor and Indra used it as a thunder weapon against giants, serpents and demons. Clearly Thor/Indra relate back to a much earlier Proto-Indo-European thunder God as they like their other Aryan cousins-the Baltic Perkunas, the Slavic Peruna and the Celtic Taranis.
Viktor Rydberg in his Teutonic Mythology volume 1 states: "The hammer is Thor`s most sacred weapon. Before Sindre forged one for him of iron[Gylfaginning], he wielded a hammer of stone. This is evident from the very name hamarr, a rock, a stone."
Ryberg in his Teutonic Mythology volume 2[Investigations into Germanic Mythology Volume II Part 1] repeats this argument: "Thor`s oldest weapon is made of stone. The name itself says so, hamarr, and this is confirmed by the folk-idea of the lightning bolt as a stone-wedge. Likewise Indra`s oldest weapon was made of stone; it is called the `celestial stone`[Rigv.II,30,5] and is said to be `four-edged`[Rigv.IV,22,1,2]. This `four-edged` weapon has its symbol in the swastika, a figure that is rediscovered in the realm of Germanic memory and therefore must have derived from the Proto-Indo-European era.
All this brings me to the passage in the Asatru Edda: "Thorr was brought up in Jotunheimr by a jarl named Vingnir, and when he was ten years old, he received the stone hammer, Vingnir`s Mjollnir."
Far from the Eddas being a mediaeval Christian monkish construction they have their origins deep into the Stone Age as this transition from a stone to an iron Mjollnir represents.