In Kant, are "pure intuition" and "intuition a priori" synonyms?

Question

I'm reading the prolegomena, and in §7, Kant presents both

• "pure intuition" (reine Anschauung), mentioned many times, and
• "intuition a priori" (Anschauung a priori), mentioned twice only.

it must be grounded in some pure intuition or other, in which it can present, or, as one calls it, construct all of its concepts in concreto yet a priori.

while the latter contains what necessarily must be met with in pure intuition, since it is, as intuition a priori, inseparably bound with the concept before all experience

The text seems to imply that all pure intuition is a priori, but could there be a intuition that is a priori but is not pure?

Answer 1

• „pure intuition“ = non-empirical intuition, intuition without object
• „intuition a priori“ = intuition which takes place before any intuition of an object

I think that Kant uses both terms as synonyms.

In §9 Kant’s emphasizes that the term refers to the form of intuition (Form der Sinnlichkeit) not to the content of the intuition of concrete objects.

Nevertheless, for me the meaning of this fundamental technical term remains unclear, see also my former question.

Possibly Kant is influenced by the traditional discrimination between causa materialis and causa formalis. Then pure intuition refers to the latter.

Answer 2

To reinforce the claim, in Paul Guyer's Kant, these are the definitions of a priori and pure in its glossary:

a priori: Known or formed independently of particular experience; non-empirical.

pure (rein): Not dependent upon actual experience, although possibly applicable to it; opposed to empirical.

These look as synonyms to me, and that this conclusion applies not only to intuitions but to all representations.