Excellent write up.
I did some soil-judging when I was in school. You can tell the type of soil by their feel between your fingers, preferably wet soil. Sand feels gritty, clay feels sticky, loam feels silky. You can also determine proportions by putting a sample into a jar, fill it half way with the soil, then fill the rest with water. Shake it up good and let it stand until all the soil has fallen out of the water... It will form layers like that. Very interesting!