Palestinians go to the Samaritans' booths along the avenue or to their homes on nearby Mount Gerizim hoping to find answers to their most pressing problems.
The Samaritans claim to be the true children of Israel who left Egypt with Moses and consider themselves the guardians of the authentic Mosaic tradition. They say it is the Jews who over time diluted the religion revealed by Moses.
Some 750 Samaritans live in the Holy Land, around half in the Israeli city of Holon near Tel Aviv, while the remainder reside on Mount Gerizim, which they consider a sacred place.
Hosni al-Samir, a 67-year-old Samaritan priest, says his people have been studying the stars for millennia.
"We have inherited astrology books for thousands of years," he told AFP. "The most recent one we use goes back almost 450 years."
The practice is restricted to the priestly class, which represents about a third of the total community, he says, adding that the use of astrology and numerology should not be confused with witchcraft or parlour tricks.
"We do not believe in sorcery, reading palms or coffee grounds or performing exorcism," he said. "All this is baseless quackery."
"We practise astrology by asking the name of the mother, the husband or wife, and we predict illness, marital breakdown or loss of work."
Samir, who started studying the ancient arts at the age of 12, says that each letter of a person's name has meaning and that the 22 letters of the ancient Hebrew alphabet used by Samaritans each correspond to a body part.
"The Samaritans have astrology books that are found nowhere else and are able to predict the beginning of each lunar month, and lunar and solar eclipses," he added.
The Samaritan capability for divination, he says, comes from their reputed descent from the Israelite tribe of Levi -- the tribe of the biblical character Joseph who, according to scripture, interpreted dreams for the Egyptian pharaoh.
-- For villagers, forecasts are unbeatable --
The priest says the split between the Israelites and Samaritans occurred when King Solomon built his temple in Jerusalem while the Samaritans insisted that the proper site of God's presence is Mount Gerizim in the biblical district of Samaria, from which they take their name.
In Nablus, local shopkeeper Akil Khalil Johari, who works next door to one of the fortunetellers' booths, says it attracts a wide array of clients.
"Palestinians, mainly villagers, consult them and are convinced that the Samaritans' forecasts are unbeatable," Johari said.
"There are Palestinians living in the United States who go to them when they visit this country."
He says the astrologers see clients for five hours starting from 8:00 am, and a preliminary consultation costs 150 shekels ($44, 30 euros) although the price of a full prediction can range from 500 to 5,000 shekels (up to $1,450/1000 euros).
Not everyone, however, is happy with the service.
Umm Firas, a 28-year-old Palestinian woman from Jerusalem, consulted the Samaritans several times in recent months.
"I went to Mount Gerizim to ask for a reading when my troubles with my husband got worse," she told AFP.
"I gave them my name, his name and those of my children and all the information they asked for.
"They put a veil on me and took from me an ounce of gold at a price of more than 2,000 Jordanian dinars ($2,817/1,985 euros)," she said.
At the session, the astrologer told her that everything would work out with her husband. But he got it completely wrong.
"I was desperate and needed an answer but it did me no good. I divorced my husband, who married a Russian woman who worked with him," she complained. "I lost my gold to the Samaritans."
But Samir says nobody is compelled to give gold.
"We tell them: 'Give what you like'," he said.
"At the end, after the priest has retired to meditate upon a solution and make calculations and analyses, and to consult the astrology books -- which can take days -- he has the right to be paid like any other business."
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