Corundum and sapphire

I recently started collecting corundum sapphires. Here in Brazil, as was the case in Montana in the United States a long time ago, there is exploitation of corundum for industrial purposes and also some for the production of low quality rubies.
I already posted some images in this forum about this and now I send some more, but now of another type, trapiche. They have several blue, grayish blue and even pink to red colors, all of them with trapiche, the largest weighs two kilos approximately. Are these stones very common or are they rare? Can someone help me?

Thank you

Mário Canevello








Mario,
I have discovered a large deposit of corundum which is very old and quite large.
Would like to speak to you about the different aspects of our finds.
Please contact me as I think it will prove interesting to us both.
I am in SE coastal Georgia.
Thanks,
Rockbuster

Hi Rockbuster,
How Can I help you?
If you want contact use marcanevello@gmail.com
Best regards

Mário

Trapiche patterns are less common in corundum, and are typically restricted to ruby.
Trapiche Sapphires are considerably rarer.

The patterns are found in almost all varieties of sapphire…yellow are very few and far in between.
Blue and black are comparatively easier to get, though still much rarer than trapiche rubies, which again, are the most common.

Dear Jacqueline,
I ask apologize because passed long time for answer. I am very thankful for your comments.
Best regards
Mário Canevello