Purple Stamp in dreams
A small piece of authorisation affixed to a document — the official mark that the thing may now travel.
How purple changes the reading
Purple colour places the symbol between hot and cool — a reading that has both calm and intensity at once. The dream often uses purple for symbols that do not fit the usual categories cleanly. Take the reading more seriously than you would otherwise; the colour is asking you to.
The base reading of Stamp
A stamp in a dream is the dream's image of the small permission that lets a piece of work leave your hands. Stamps are not the writing; they are the authorisation that the writing is ready to be sent. The dream brings the stamp when something you have prepared — a letter, an application, a decision — is finally being released into the world. A stamp affixed and the envelope leaving the house is the dream marking the release. A stamp held but never applied is the dream noting that the work is ready and the permission has been written, but you have not yet let it go.