[Request] How to accurately pick up items with Python colour bot

I wrote a bot to afk vyres and pick up the bloodshards but my bot keeps randomly missing them on the floor and letting them spawn to other players. I lost 3 shards in one session because of this. I'm not going to explain my method because I don't actually know where it's failing, but tl;dr I'm using the colour of the item drop, finding the mid point and left clicking on it. Obviously, this has proven to not be reliable. What colour bot methods are you guys using?