Eucratidea or Alexandria-on-Oxus (Oxiana)

Established ~ 300 B.C. and destroyed ~ 145 B.C. This is the easternmost end of the Bactrian Plain, where river Oxus meets the Kokcha river (the lapis mines are up this river). The plain is exceptionally fertile where everything but olives can grow.
Oikistes is Kineas. His sarcophagos had survived.
Items that had survived when it was excavated by the French: two types of sundials, royal hall had 18 Corinthian capitals, also 60 Doric columns in the gymnasium. The theatre had spacious, honorary seats, half-way up the rows of seats. Some pages of a lost treatise of Aristotle were found, mosaics used stones from the nearby river, storage with iron armor, Megarian bowls and gold ingots from melted-down objects.
Philosopher Clearchos of Soli, a pupil of Aristotle, visited here and brought with him a copy of the Delphic Precepts which was engraved on the funerary monument of Kineas.
"These wise sayings of the illustrious men of old have been concecrated at the sacred Pytho. There, Clearchos transcribed them carefully coming here to display them so that they shine in such a distant place, in the sacred precinct of Kineas.
                                            AS A CHILD LEARN GOOD MANNERS
                                           AS A YOUNG MAN LEARN TO CONTROL THY PASSIONS
                                            IN THE MIDDLE AGE BE JUST
                                          IN OLD AGE GIVE GOOD ADVICE, THEN DIE WITHOUT REGRETS

Bactrian Greek kings /queens and Indo-Greek kings / queens

Demetrios 1st

Euthedemos

Demetrios 2nd

Antimachos

Eucratides

Pantaleon

                                                                          Agathocles

                                                                       Agathocleia

Amyntas Nikator

Apollodotos

Artemidoros

Epandros

Hippostratos

Menandros

Menandros Dikaios

Philoxenos

Polixenis

Straton 1st

Alexander the Great's gold = 2,500 tons +

This amount of gold was discovered by Alexander after he conquered Persepolis.
Where did the Persians find their gold that Alexander inherited ?
The nearest source of gold is the Tien Shan Gold Belt that extends from Uzbekistan, through Tajikistan / Kyrgyzstan into China. This belt has the largest concentration of gold in the world after the South African Witwatersrand deposits. Some of the valleys in Tajikistan have alluvial gold, such as the rich Darvaz deposit on the north bank of the Oxus river.
The Persian Empire was extremely rich in gold reserves and thus able to finance its expansions and its dealings with other tribes. Expedition to conquer Greece ? No problem, the money was there!
Later on, the Bactrian Greeks with their prosperous "one thousand cities" had a thriving Empire that extended into the fertile Ferghana Valley and managed to reach and trade with the Chinese for the first time probably around 220 B.C. The Chinese marveled at their "heavenly horses", their manufacturing abilities and love for wine. They called the Greeks "Dayuan" or the Great Ionians. In return, the Greeks adopted methods of metal casting and the use of a new metal in coinage : Nickel, which was in use in China at the time and was called "white copper". A direct result of this, the Silk Road was developed in the 1st century B.C. and it passed through this already opened road of communications: The Ferghana Valley and the city of Marakanda or Samarkand.
The picture above is from the museum at Urumqi, China depicting a Greek soldier from a 3rd cent. B.C. burial site.