Why Did These Have Radioactive Material Added?

In this video I talk about this table full of radioactive uranium glazed ceramics...why did these have radioactive material added to them?

Patreon Thanks:
https://www.patreon.com/radioactivedrew
(Gamma Radiation Tier)
Brennen Boyer
K Taylor
Don Reyes
Matt Pickering
Nathan McNab

Radeye B20:
https://www.fishersci.com/shop/products/radeye-b20-b20-er-multi-purpose-survey-meters/p-4531281

Camera Equipment Used

Camera Used in this video:
Sony A7S3 https://amzn.to/3WZsU53

Lens Used:
Sony 16-35mm f2.8 https://amzn.to/3Gg6vub

Lens Used:
Sony 50mm F1.2 https://amzn.to/3W0sfiQ

Variable ND Used: https://amzn.to/3g2PPvN

Wireless Mic Used: https://amzn.to/3WK5gZ2

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