Purple Pen in dreams
An ink-bearing writing tool — the means of recording what you mean, in your own hand.
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 Pen
A pen in a dream is the dream's image of the means by which an inner intention becomes a recorded line. Pens commit; what is written in ink is harder to retract than what is written in pencil. The dream brings the pen when something in your life — a decision, a confession, a signature — is ready to be put down in a form that will outlast the impulse. A pen writing cleanly is the dream telling you the moment of commitment is the right one. A pen that has run dry is the dream noting that the will to commit was there but the resource — energy, conviction, courage — has run out at the wrong moment.