As a calf continues to grow, so does it's horns. You could compare their horns to our ears and noses. They never stop growing throughout our life. The same goes for Longhorn cattle. As you can see in this picture, it's almost like a rainbow of colors. At the base the horns look almost yellow. Then as you go outward you see more yellows, tan, white, purple, and finally a pink! The pink indicates good blood flow. Which is what you want to see in a young calf. Big John although not a young calf, has not reached his full potential yet. So we will continue to see his obvious horn growth for a few years. Just like when we get older the changes are not as subtle, the same goes for cattle. When they are fully grown it is hard to tell by merely gazing upon them if their horns have grown or not. Big John being a steer also contributes to his continuous growth. Meaning that all his energy and hormones are going towards horn and size production rather than reproductive matters.
Every animal is unique in their own way. Cattle in particular. There will always be that one little aspect that sets them apart from the others. Unlike Angus cattle, Longhorn cattle differences are far more noticeable. Not only be their color differences, but by their horns! After all, that is what they were named for! That's also the first thing here at the farm we look at when purchasing. "Man look at that set of horns!" is often thrown around as common phrasing.