1) Start with the easiest baseline: Copper

• Copper plugs have a big, fat center electrode (he jokes it looks like a “pinky”).

• Key takeaway: copper is visually obvious and has no recoverable precious metal value for their program.

2) Iridium vs Platinum: what the center electrode looks like

• Iridium = fine-wire style center electrode (thin, needle-like).

• Platinum = between copper and iridium:

  • more like a wire but with a wider base

  • they describe it as looking like a “Hershey kiss” sometimes.

3) Read the ceramic label when manufacturers make it easy

• Some plugs literally say “IR” / “IRL” / “Iridium” or “Platinum / Double Platinum” on the ceramic body.

4) Ink color can be a clue (not perfect, but helpful)

• They mention blue or green ink often correlates with precious metal plugs (platinum/iridium).

• Black ink can still be platinum/iridium sometimes, so it’s not a hard rule.

5) What Noble6 is accepting for recycling

• They’re accepting automotive spark plugs that are iridium or platinum based.

• They explicitly say: copper tips have no value and should be kept out.

6) Keep the bins clean (very specific warnings)

• Keep trash and other scrap out of the bin.

• They’ve received drums with motor oil in them, which causes problems on their side.

7) Send plugs “whole,” not partial

• Their system uses vision learning / cameras + automation to detect orientation and processing direction.

• Partial plugs confuse the system/PLC, because the camera can’t reliably detect direction.

• So they need whole plugs for the system to work correctly.

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