The VOC and the Dutch quest for silver.
The first Dutch expedition set sail for the East Indies in 1595 to access spices directly from Asia. When it made a 400% profit on its return, other Dutch expeditions soon followed. Recognising the potential of the East Indies trade, the Dutch government amalgamated the competing companies into the United East India Company (Vereenigde Oost-Indische Compagnie or VOC).
The VOC was granted a charter to wage war, build fortresses, and make treaties across Asia. A capital was established in Batavia (now Jakarta), which became the center of the VOC's Asian trading network.
To their original monopolies on nutmeg, peppers, cloves and cinnamon, the company and later colonial administrations introduced non-indigenous cash crops like coffee, tea, cacao, tobacco, rubber, sugar and opium, and safeguarded their commercial interests by taking over surrounding territory.
The flow of foreign money was greatly diminished due to fighting between Spain and the Dutch and English. The Spanish rulers tried to have the silver of the Americas brought directly to Spain instead of being exported to the Ming Empire. This raised the price of silver sharply.
Then in 1639, a Japanese Shogun limited foreign imports as part of his isolationist policy. This further limited the empire's trade and contributed to the Ming Empire's monetary crisis. The value of silver jumped markedly. This reduced the profit margin in the flow of Spice to Europe.
By the year 1800 the English East India Company was shipping more than 23 million pounds of tea annually. Since the Chinese were not interested in English goods, a terrible trade imbalance existed. This deficit was nonetheless a flow of silver bullion out of England and into China.
Silver, minted by the Spaniards in their new territories in the Americas eventually travels across the Pacific, through Manila, and into China as the commodity the Europeans can trade for the goods they seek from China (the Spanish or "Mexican dollar").
China becomes a "sink" for silver.
Not having silver, and wanting to gain control, the English East India company introduces opium to China. By 1830, over 50% of trade is paid for with Opium. China becomes an exporter of silver to pay for the Opium, English have their tea, and destroy the Chinese market.
Keep in mind that the Spice bought in China and the East sold in Europe for 100 times the purchase price, not 100% ...given that silver was already at a 2 times value than Europe, you can see why the trade was so lucrative, and back to the original post, why there would be no silver coming on the return trip.
More at
https://en.wikipedia.org/wiki/Dutch_East_Indies
