MICROSCRAPPINGE-waste field guide
Other · Tier D

Nixie Tubes, VFDs & Dekatrons

If it has ten stacked wire-mesh numerals inside a glass envelope it is a $15–350 collector part and its scrap value is under ten cents — the metal question is not a question.

Base nickel cathodesBase tungsten filament (µg) in VFDsBase total metal value $0.02–0.15 per tube
eBay typical$150–900per lb
Refiner pays$0per lb
Metal in it$0.000per lb at 4 Aug 2026 spot
Confidencehighof the yield figures

How to spot it

Glass envelope 15–65 mm in diameter. Nixies show ten overlapping wire-formed digits 0–9 stacked front-to-back behind a fine mesh anode, glowing orange-red; top-view types are IN-12 and ZM1020, side-view IN-14, IN-18 and B-5750. VFDs are flat glass with blue-green planar segments and a fine horizontal filament wire visible across the face. Dekatrons show a circular ring of 10 or 30 cathodes in a flat disc. Cyrillic markings (ИН-14, ИВ-18) mean Soviet; Burroughs, RCA, GE, Hivac, Mullard and RFT are Western. Found in 1960s–70s counters, DVMs, nuclear scalers, calculators and cash registers.

Metal content

MetalQuantityNotes
Base metalnickel cathodes, 0.3–1.5 g per tubeAnode grid nickel or stainless; pins kovar/Ni-Fe with sub-milligram gold flash at most
Base metaltungsten filament (µg) in VFDsGraphite/ZnO:Zn phosphor anodes, nickel grid mesh
Base metaltotal metal value $0.02–0.15 per tubeNo Au, Ag or Pd worth naming

Safe removal

Working temperature: Hot air / iron 330–350 °C

Desolder, never pull. Wire-lead tubes need each lead desoldered individually at 330–350 °C with a low-flow sucker while supporting the tube — the glass-to-metal seals crack under lateral force. Socketed tubes: rock the socket, never the glass. VFD filaments are under tension and break invisibly from a bump. Cut the board around a stubborn joint rather than fight it; clean flux with IPA, never ultrasonically.

Hazards

☢ Radioactive materials

NEVER grind, sand, saw or incinerate anything that might contain thorium or radium. Sealed sources stay sealed.

🌡 Mercury

NEVER vacuum a mercury spill — it aerosolises it. Use a mercury spill kit or sulphur powder, or call your local hazmat line.

🩹 Glass and sharps

NEVER blow on, wipe with bare fingers, or brush away cut optical fibre.

⚡ Stored high voltage

NEVER short a large capacitor with a screwdriver. It welds the tip, blasts molten metal at your face, and can rupture the can.

Before you scrap it

Infinite multiple — scrap value is zero, so any working tube is pure upside. A tested and matched set of six IN-18s is $540–700 against $300–400 untested; testing and matching adds 40–70%. Uneven digit brightness means cathode poisoning and a 50% discount. Original 1960s instruments with tubes still fitted often sell for more intact than the tubes fetch individually.

The common trap

Old tubes are full of gold or platinum. They are nickel and glass. The broader myth that vacuum tubes generally carry precious metal is also false — the exceptions are a handful of transmitting tubes with gold-plated grids, and those are worth more as tubes anyway. Second trap: assuming Soviet NOS stock is infinite; IN-18 and Z568M stockpiles are exhausted and prices have risen 3–5× in a decade.

Questions

How much gold is in nixie tubes, vfds & dekatrons?

There is no meaningful recoverable precious metal in this item. Old tubes are full of gold or platinum. They are nickel and glass. The broader myth that vacuum tubes generally carry precious metal is also false — the exceptions are a handful of transmitting tubes with gold-plated grids, and those are worth more as tubes anyway. Second trap: assuming Soviet NOS stock is infinite; IN-18 and Z568M stockpiles are exhausted and prices have risen 3–5× in a decade.

How do you identify nixie tubes, vfds & dekatrons?

If it has ten stacked wire-mesh numerals inside a glass envelope it is a $15–350 collector part and its scrap value is under ten cents — the metal question is not a question.

How do you remove nixie tubes, vfds & dekatrons safely?

Desolder, never pull. Wire-lead tubes need each lead desoldered individually at 330–350 °C with a low-flow sucker while supporting the tube — the glass-to-metal seals crack under lateral force. Socketed tubes: rock the socket, never the glass. VFD filaments are under tension and break invisibly from a bump. Cut the board around a stubborn joint rather than fight it; clean flux with IPA, never ultrasonically.

Is nixie tubes, vfds & dekatrons worth more working than as scrap?

Infinite multiple — scrap value is zero, so any working tube is pure upside. A tested and matched set of six IN-18s is $540–700 against $300–400 untested; testing and matching adds 40–70%. Uneven digit brightness means cathode poisoning and a 50% discount. Original 1960s instruments with tubes still fitted often sell for more intact than the tubes fetch individually.

Related in Other

Get this offline → The full guide runs in your browser with no signal, and you can add your own photos.