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enderjaca t1_j2emudj wrote

Reply to comment by sgarn in How did Rutherford arrive at gold foil as the best choice for his particle experiments? by Poltibolsa

>with gold foil more ubiquitous than lead foil

Just to clarify, that doesn't necessarily mean that gold is found more commonly than lead, it's that gold foil was relatively easy to make compared to lead foil? Is that still true today?

I recall selling and using adhesive lead foil for adjusting the weight and balance of tennis racquets, for example. Most modern commercial uses of gold foil I've noticed seem to be related to artistic projects or embellishing food at fancy restaurants.

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a_wild_redditor t1_j2eojab wrote

Gold leaf is readily available very thin, it can be well under 1μm. The lead sheet or foil I'm familiar with is much thicker since common uses require its density (counterweighting as you mentioned), its radiation shielding properties, and/or its easy formability by hand while holding its shape afterwards.

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LittleLostDoll t1_j2f3ufs wrote

if yoiu up lead baloon on youtube adam savage talks about when they wanted to see if they could get a lead baloon to float they were having trouble getting the lead thin enough, and two companies broke their machines even try

this ws about 15-20 years ago but id think even today it isnt much thinner than they were able to get back then

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Kraz_I t1_j2f8byk wrote

Gold is the most ductile and malleable of all pure metals (and probably alloys too, since they tend to be harder and more brittle). This is why it's used in computers and advanced electronics, even though silver and copper are more conductive. A very small amount goes a long way, it can still hold together at under 1 micron thickness.

If you tried to hammer lead into a foil that thin at ambient temperature, (which is the traditional way gold foil is made), it would crumble to bits.

Even in antiquity, artisans knew how to make very thin gold foil by hammering it thin, then folding it with paper between the layers to prevent cold welding, and continuing the process, with the number of layers doubling each time.

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