A more familiar common use is in silver-coloured modern circulation coins. A typical mix is 75% copper, 25% nickel, and a trace amount of manganese. In the past, true silver coins were debased with cupronickel. Despite high copper content, cupronickel is dark bronze in colour when in storage, but is a light copper colour when polished. Thermocouples and resistors whose resistance is stable across changes in temperature contain the 55% copper-45% nickel alloy constantan.
For the past 3 months, I've been taking several popular nootropics in relatively recommended dosages. The results have been generally positive (mental stamina, desire to learn, impressive thoughts at times), however, I am experiencing the following unwelcome side-effects. -Rash and skin irritation.
Note: The aforestated side effects refer to unwanted and/or bizarre experiences associated with noopept, not general effects (e.g. improved learning) which may be of therapeutic benefit. Also understand that noopept users are unlikely to experience every single side effect listed above; certain users may experience no side effects at all.