I don't quite understand this bitcoins thing.
The supply side dynamic of gold and silver is heavily influenced by mining difficulty. Ore grades keep diminishing, especially for silver, and miners are holding onto their supply if the price is too low.
Apart from industrial and jewellery demand, gold and silver can also be valued according to the cost of labour to mine at the time of valuation. This is why precious metals have a long-term uptrend in valuation, due to increasing mining difficulty.
10 years from now a lot more energy and labour would be require to mine an ounce of silver or gold than today. Hence, one may think of precious metals as representing energy or labour. Bitcoin also represents expended energy and labour that is/was required to bring every coin into existence. Each coin is a proof of work.
What makes cryptocurrencies like Bitcoin and Litecoin different is that it does not have direct industrial or adornment demand, it is also not tangible in the physical sense. Bitcoin is tangible in a logical, informational and scientific sense though, as every coin is explicitly tracked and accounted for in a decentralized manner.
Bitcoin is designed from the ground up to have complete transparency and robustness. A 51% attack is possible, but the miners actively avoid having a majority share because it would destroy the currency and their holdings.
When the Bitcoin money supply expansion is stopped at 21 million BTC then each bitcoin will represent an infinite amount of energy required to bring it into existence. Wrong, that doesn't make practical sense. The value of a bitcoin will then only be in its trusted role as a medium of exchange, and processing power will be rewarded solely by transaction fees.
Bitcoin investment is risky at best, especially at this +$100/BTC value. Yet, even at this relatively late stage there is still much potential, and I guarantee that there will be many players making 100 baggers over the next 3 years, if they know where to invest their play money in this virtual market. There will also be a lot of losers, so I only play with what I can lose.