In the autumn of 1633, a trade mission heavily laden with gifts headed east from northern Germany. The great duke of Holstein was sending an ambassador to Moscow to request the czar’s permission for travel rights along the Volga River. Holstein was the northernmost tip of the Holy Roman Empire, in many ways more closely tied to Scandinavia than to their Habsburg overlords. This expedition was part of an attempt to establish an inland silk-trade route between Europe and the Orient. Such a route would eliminate the circumnavigation of Africa, shortening the trip and reducing risk. After several years and initial high hopes, it became clear that the effort was doomed to failure. Czar Michael I of Russia was enthusiastic about the project, but at the southern end of the route, the king of Persia was not so receptive. Nevertheless, the expedition did become famous for a different reason: a written account of the adventures of the diplomats.
Upon the delegation’s return to Holstein, their secretary Adam Olearius (1599-1671) published a book that chronicled their travels.  As a mathematician, astronomer and general polymath, Olearius provides an uncommon perspective of the various cultures, practices and technologies encountered. Ultimately, he was appointed royal librarian and keeper of the duke’s cabinet of curiosities. The book proved so popular that more comprehensive editions soon followed, adding the contemporary accounts of another traveler, Johann Albrecht von Mandelslo. 
Glass is not the central theme of his adventures, yet this and related subjects are discussed in a number of different passages, giving us a unique insight into the material’s place in those societies.
In August of 1634, the group arrived in Moscow. Having been granted audience with the czar, Olearius describes the procession of the entourage and enumerates a long list of the gifts they brought. Among them was “a great looking-glass, being an ell and a quarter high and half an ell broad, in an ebony frame, with boughs and fruits carv'd thereon in silver, carried by two Muscovites.”  An ‘ell’ was the northern european equivalent of a cubit or about 25 inches, so the mirror measured about 12 inches wide by 30 inches tall, not enormous by current standards, but quite an achievement in the seventeenth century. Glass workers would have to blow a large cylindrical bubble, cut it open and lay it flat on a polished marble surface. To be usable, the sheet of glass would have to be made without waves or defects and it would have to be cooled slowly, over a period of many hours in order not to form cracks. Silvering the back was a whole other ordeal performed by an artisan schooled in alchemy.
Speaking of the chemical arts, gifts from the duke of Holstein to the czar of Russia also included “an ebony cabinet, garnish'd with gold, like a little apothecaries shop, with its boxes and vials of gold, enrich'd with precious stones, full of several excellent chymical extractions, carried by two Muscovites” 
While in Moscow, Olearius put on a demonstration of optics for some locals. “I shew’d them upon a wall of an obscure chamber, through a little hole I had made in the shutter of the window, by means of a piece of glass polish’d and cut for optics, all was done in the street, and men walking upon their heads: This wrought such an effect in them, that they could never after be otherwise persuaded than that I held a correspondence with the devil.”  Here he is describing a ‘camera obscura’ in which scenes from outside are projected upside-down onto the wall of a darkened room.
A couple of years later, after a return to Holstein to ratify a treaty with the czar, the delegation arrived in Persia. They were treated to a sumptuous meal by the king’s chancellor. “The walls were all set about with looking-glasses, to the number of above two hundred, of all sizes. So that when a man stood in the midst of the hall, he might see himself of all sides. We were told that in the king’s palace, in the apartment of his wives, there is also a hall done all about with looking-glasses, but far greater and much fairer than this.” 
“For the teaching of astronomy they have neither sphere nor globe, insomuch that they were not little astonished to see in my hands a thing which is so common in Europe. I asked them whether they had ever seen any such before. They told me they had not, but said that there was heretofore in Persia a very fair globe which they call ‘felek’, but that it was lost during the wars between them and the Turks. They haply meant that which Sapor, king of Persia, had caused to be made of glass, so large, that he could sit in the center of it, and observe the motions of the stars and must no doubt be like that of Archimedes, where of Claudian speaks in the Epigram which begins thus: Jupiter in parvo cum cerneret aehera vitro.” 
Olearius goes on to describe the Persian army in some detail, including this account of an early form of chemical warfare. “At the siege of Iran, in the year 1633, they had the invention of casting into the place with their arrows, small glasses full of poison, which so infected the air that the garrison was extremely incommodated thereby and made incapable of handling their arms for the defense of the place.” 
In 1637, near Tehran, Iran, he describes a royal tomb “adorn’d all about with glass of all sorts of colors, which are preserved by iron grates.”  And in the same area,
“At Kimas, in the province of Kilan, there was one of these mountebanks, who having found out the trick of setting cotton on fire by means of a crystal cut in half-round and held in the sun like a burning-glass, would have people persuaded that by operation, which he affirmed to be supernatural, that he was of the kindred of Mohammed. After our return to Holstein, I shew’d the Persians, whom Schach-Sefi [king of Persia] sent thither, that it was the easiest thing in the world to get fire from the sun, and I lighted paper in the very depth of winter by means of a crystal full of cold water, or a piece of ice, which I had made half round in a pewter dish. They were astonish’d at it, and said, that if I had done as much in Persia, I should have pass’d there for either a great saint, or a sorcerer.” 
As an addendum, in later editions of Olearius’ book, the recollections of Johan Albrecht de Mandelslo (1616–1644) were added. He accompanied an unrelated trade mission to Isfahan,Persia, and then split from his group to continue touring the region. He traveled through India, and then down the African coast. In 1639, the German traveler passed through Madagascar. He commented on the inferior quality of European glass trade-beads, compared to those of India, which he acquired earlier in the trip.
“The glass-bracelets, beads and agates, we had brought from the Indies [India] were incomparably beyond what they were laden with out of Europe; so that it was resolved ours should not be produced, till the others were sold. By this means, we bought every day four oxen for forty pair of glass bracelets, which the inhabitants call ‘rangus’; a sheep for two, and a calf for three ‘rangus’; and for a brass ring, ten or twelve inches about, a man might have an ox worth here six or seven pound.” 
Much has been made of the use of glass trade-beads by Europeans around the world.
In Madagascar and along the trade routes of the Indian Ocean, European traders were fairly late to the party. For a thousand years earlier,  beads had been used as the currency of choice among disparate cultures from Indonesia and China to India to Africa who did business with each other. The above quote from Mandelslo’s diary provides a fascinating firsthand account of transactions with beads. The passage also hints at the superior quality of Indian glass beads. Today, glass beadmaking continues on an industrial scale there, and the glass bracelet industry still survives, notably in Firozabad, northern India.
 Adam Olearius: Beschreibung der muscowitischen und persischen Reise
 Adam Olearius, John Davies, Johann Albrecht von Mandelslo, Philipp Crusius, Otto Brüggemann: The Voyages and Travells of the Ambassadors Sent by Frederick Duke of Holstein, to the Great Duke of Muscovy, and the King of Persia...
: John Starkey, and Thomas Basset, 1669).
 Ibid, p. 58.
 Ibid, p. 212-213.
p.252. Jupiter in parvo quum cerneret æthera vitro
[When Jove a heav’n of small glass did behold,] see Henry Vaughan: Silex scintillan, Hermetical physick, Thalia redivava, Translations, Pious thoughts and ejaculations
. (Oxford: Clarendon Press, 1914) v. 2, p.635.
 For example warring states beads in China
, see https://en.wikipedia.org/wiki/Ancient_Chinese_glass
 Carla Klehm has a nice post on the subject of trade beads used around the Indian Ocean
; see “Trade Tales and Tiny Trails: Glass Beads in the Kalahari Desert
” in The Appendix,
Jan. 2014, v. 2, n. 1. http://theappendix.net/issues/2014/1/trade-tales-and-tiny-trails-glass-beads-in-the-kalahari-desert