When learning about the Silk Road, we all heard of the interesting and useful things coming from Asia. Silk, spices, animals, porcelain, technology, etc. But there's little account of what came from Europe, besides gold. Wouldn't it have been a massive drain on the wealth of European nations to be bringing in all these things and not making any profit for themselves? And isn't Europe relatively resource poor in things like gold and gemstones too?
If this is the case, how did they sustain trading hard currency for fragile or exhaustible goods for over a thousand years? Did any notable people of the time have opinions on this subject? Here's hoping someone knows more about this subject and can shed some light on how the trade worked back then.
You've identified what was pretty much the central problem European traders faced for the entirety of the medieval and early modern periods. Europe had very little to sell that the rest of the world wanted to buy. The primary luxury good Europeans had to sell was furs. Virtually the only manufactured good that the Europeans had to offer that was attractive for sale overseas were swords and weapons (eventually guns). To make this picture even more complicated, not only was Europe importing luxuries like silks and spices but it was also apparently at the receiving end of Arab gold and silver.
So what the hell were the Europeans trading?
One solution in the Medieval period was to export slaves. As McCormick writes in that essay:
In some not unimportant measure, Europe financed the early growth of its commercial economy by selling Europeans as slaves to the Arab world.
I'm less familiar with period in between, but eventually that trade was, however, halted while the European demand for such goods continued to grow.
The discovery of the new world was one partial solution to the problem in that it provided huge new sources of gold and silver which would eventually head west to Asia to purchase luxury goods there, but the basic problem of China and other east Asian powers simply not wanting anything that Europeans had to offer other than precious metals persisted. Europeans were keenly aware of this as being a problem, which in some ways is the basis for mercantilism.
On the other hand, the volume of trade between east Asia and Europe was small before 19th century. That trade expanded and an eventual "solution" found in "triangular trading" that saw, for example, Britain growing opium in India to exchange in China for tea that would then be sold in Britain for the profit of the British merchants. Or the perhaps better known Atlantic triangular trade.
The industrial revolution combined with the emergence of a bulk trade in cotton from America also meant that for the first time European textiles were cheap enough and of a suitable quality (as opposed to less desirable woolens) that there was demand for them in Asia.
In terms of further reading, I would have a look at John Darwin's After Tamerlane which does a very good job of looking at these economic developments, in addition to the essay I linked to above.