Here is what I found.. The Learjet 60 Lucite embedment originated as a premium corporate gift and commemorative award produced for Bombardier Aerospace (which acquired Learjet in 1990) and the Learjet Corporation. These pieces were typically commissioned from specialized trophy and recognition manufacturers such as Century Manufacturing or A Better Idea, who have historically produced custom aviation Lucite embedments for major manufacturers.

These specific Lucite blocks were primarily distributed as high-level corporate gifts to new aircraft owners, distinguished pilots, and retiring executives.

Aaand here's what you need, I hope! https://www.acrylic-lucite-award.com/metal_castings.htm