At the moment, there is something of a boom for goshuin in Japan.
A goshuin is a vermilion stamp that you can receive at a jinja or Buddhist temple to record the fact that you visited there and paid your respects. They were originally Buddhist, and recorded the fact that you had copied and offered a sutra. I am not sure how they work at Buddhist temples these days, but at jinja they are a record of your sanpai: visiting and paying your respects to the kami. In theory, you should formally pay your respects at the jinja before getting the goshuin, and you cannot get them for other people, because those people have not visited the jinja. At one jinja, which offered goshuin for all the subsidiary jinja in the precincts (at ¥300 each, the standard offering), I was told to go and pay my respects to any I hadn’t visited yet while they were preparing the goshuin.
The normal procedure is for a priest at the jinja to write the name of the jinja, “hōhai”, which means that you paid your respects, and the date on a page of your special goshuin book, called a goshuinchō, and then stamp a red seal over the top. People collect them in these books, and in some cases collect the books. My daughter and I both have a fair number of them.
A few weeks ago there was an article in Jinja Shinpō wondering about what was going to happen to these books in the future. The author had helped write Jinja Honchō’s guidance on goshuin a few years ago, but the boom has become much larger than anticipated, and he did not really give any thought to what should be done with the books when the owner died.
One issue is the status of a goshuin. Some people treat it as like an omamori, containing the spirit of the kami. That is certainly not universal, and Jinja Honchō’s official position is that it isn’t quite like that, but everyone agrees that they are not just souvenir stamps. They have some religious significance. The author of the article thought that they should, ideally, be taken to a jinja, and then burned in the formal ceremonies in which old omamori and ofuda are burned.
On the other hand, he also mentioned that he has about ten goshuinchō from the Tokugawa period (before 1868), and observed that these were now important historical documents. Not only are they a dated record of which jinja and temples that person visited and when, they also record the forms of the goshuin of those institutions. Thus, as with many things, the ones that people can keep are likely to become valuable in time.
The author concluded by asking that people raise awareness of the principle that goshuinchō should not just be thrown away like any other waste paper, but should rather be disposed of at a jinja, as their “sacredness” should be understood and respected. This reflects a constant concern in the Shinto world: that jinja not become simply another tourist attraction.
A neighbour once mentioned that when his grandmother died it was her wish to take her goshuin with her, so they were put into her coffin and cremated with her.
I read somewhere (but I have no idea how reliable this is) that the original idea behind the Buddhist Goshuin was that they acted as a kind of visa for the afterlife, getting you into the nicer parts. In that case, having the goshuinchō cremated with you would make a great deal of sense. Officially, the Shinto ones do not have that sort of connection, but it is the sort of belief that could easily get passed on independently. Thanks for the interesting comment!