You only need a very little amount of red or black oxides for colorant( but you know that now). The other oxides you can use more to achieve the color you are looking for but not the red and black. Start by adding your colorant by drops til you get the color you want, you can always add more but can't take it away.
Unless your ingred were miscalculated, why on earth would you throw those in the trash - they are pretty. Some people like the earthy colors. I had learned long ago, what I didn't like others have loved. So don't throw them out, JMO