Before art school I’ve never heard of this phrase: formal quality.
“Formal” refers to the visual building blocks of piece of art that you are looking at. Form starts with dot, which when it moves leaves a line, which when it closes onto itself completes a shape. Form also includes things like depth, texture, and color. So one day you could ask “what do you think of the formal qualities of this piece,” your artist friend will likely start to break down the artwork in terms of dots, line, shape, depth, texture, and color. It’s really interesting to see what you will learn.
My images are very simple in terms of forms. That is why they are restful and quiet. There is not a lot going on in them. Of course, the predominant form in my images is color. I think that blue opens the door to contemplation and silence, and that is what the images are meant to do.
“Formal quality” of an artwork then is the cumulative effect of all the formal elements in the artwork. Taken together, is the formal quality one of serenity or loudness, is it light or dark, soft or hard, smooth or rough?
More importantly, how does the artwork make you feel? That feeling is created in part by the formal quality of the artwork. It’s magic.