Other · Tier C

Vintage & Graphing Calculators

Red LED digits or a glowing blue-green VFD means 1970s — gold-era board inside and a collector market outside. LCD means check the model before doing anything.

Au 0.05–0.30 g/lbBase NiCd packs in early rechargeables

eBay typical$20–150per lb

Refiner pays$2per lb

Metal in it$19.6per lb at 4 Aug 2026 spot

Confidencelowof the yield figures

How to spot it

The money list: any HP with RPN (HP-35, 41C, 42S, 12C), TI-58/59, Curta-adjacent oddities, Sinclair, and desktop Nixie/VFD calculators (Friden, Wang, HP 9100). Steady sellers: TI-83/84/89, HP 48/50. Landfill: 90s+ four-function and solar credit-card calculators.

Metal content

Metal	Quantity	Notes
Gold	0.05–0.30 g/lb, 1970s only	LED-era boards with gold-plated keyboard domes and DIP chips — estimated, model-dependent
Base metal	NiCd packs in early rechargeables	Leaking cells corrode the board — remove on sight

At 4 Aug 2026 spot prices that works out to $19.6 per lb of contained metal — Gold 0.15 g = $19.6. A refiner paying $2 per lb returns about 10% of that, which is normal: refining costs money and the buyer takes a margin.

Safe removal

Working temperature: No heat needed — mechanical teardown only

For true scrap units: four to six screws or snap posts, pull any NiCd pack, board out whole — 1970s boards go to gold-era board stock, keyboard dome sheets are often gold-plated on the good makes. Desktop Nixie calculators should never be scrapped — the tubes alone outvalue the metals 20×.

Hazards

☠ Lead — dust more than fume

NEVER dry sweep or use compressed air on a scrapping bench. HEPA-vac or wet-wipe only.

Before you scrap it

HP RPN models $50–500+, HP-01 watch calculator $1,500+, Nixie/VFD desktops $100–400, TI graphing $20–45 all day, Sinclair Scientific $80–200. Even dead HPs sell for keyboards and cases.

The common trap

An HP-41C with modules is a $150–500 item and even common HP-12Cs bring $30–60 forever — the gold on any calculator board is under $2. Battery corrosion is the value killer: pull cells from every unit the day it arrives, and grade corroded HPs as parts, which still sell.

Questions

How much gold is in vintage & graphing calculators?

Gold: 0.05–0.30 g/lb, 1970s only. At current spot that is about $19.6 of contained metal per pound.

How do you identify vintage & graphing calculators?

Red LED digits or a glowing blue-green VFD means 1970s — gold-era board inside and a collector market outside. LCD means check the model before doing anything.

How do you remove vintage & graphing calculators safely?

Is vintage & graphing calculators worth more working than as scrap?

HP RPN models $50–500+, HP-01 watch calculator $1,500+, Nixie/VFD desktops $100–400, TI graphing $20–45 all day, Sinclair Scientific $80–200. Even dead HPs sell for keyboards and cases.

Related in Other

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