The Plato forms are not dependent on the mind and hence they are not mind entities. They are not dependent on the mind to grasp them for their existence but their existence is grasped by the mind. These forms are used to solve problems like the metaphysical, moral, Epistemological and Semantical which are types of philosophical problems. Sometimes Plato argues for the existence of the form and sometimes he writes about the form in such a way that only he doesn’t believe in the existence of the forms. Plato always has some sort of connection with these forms in his mind to play.
There are many sample forms which are available on the internet and these are free forms which you can download. Then you will see that during every argument Plato was not at all systematic regarding his point. According to him the forms are recollection and these provide the objective for moral concepts. There are many other arguments which Plato has given related to the form and its existence. The arguments given by the Plato is very important as it tell the problems which are solved by the forms. These are very complex theories and if anyone wants to understand it needs to go through it very thoroughly.