"A piece of living history," says Sarah, pointing to the colorful Berlin Wall pieces that are set up on a table in a souvenir shop in Berlin. Visiting from Sweden, Sarah is strolling down Berlin's Unter den Linden boulevard with her mother and thinks it is "cool" to take a piece of the Berlin Wall back home.

As if they were precious stones, the pieces are sealed in plastic bags. Prices vary from 6.99 euros to 23.99 euros ($7.80-26.76). None of the mini chunks is cut smoothly. They're jagged, as if they've just been broken out of the wall.

Affordable pieces of history

The pieces sell very well. For souvenir vendors in Berlin, they're still a good deal. After refrigerator magnets, they are the second-best selling item, the shop owner says, "One in five visitors buys a piece of the wall."

Wieland Giebel, the head of Berlin Story, a bookshop that also sells online, confirms that interest is high. In his four Berlin stores and online shop, he makes hundreds of thousands of euros each year selling bits of the wall, he told DW. He added that demand has remained consistent over the years.

Giebel describes himself as "the largest retailer of parts of the Berlin Wall in the world." In addition to the smaller pieces, he also offers massive concrete segments for 7,000 to 12,000 euros. Those buyers tend to be corporations or large institutions, he said.

Still, Giebel does the bulk of his business with the smaller wall souvenirs. Interest tends to peak around the date of the anniversary of the fall of the Berlin Wall on November 9. The anniversary of the beginning of the wall's construction, August 13, is less celebrated.

Only one kilometer sold

According to the Federal Foundation for the Reconciliation of the SED Dictatorship, more than 360 complete segments of the Wall have been sold since it was brought down. "This corresponds to a length of one kilometer," Anna Kaminsky, an expert from the foundation, explained.

Theoretically, that means 154 kilometers (over 95 miles) of the wall should still be available. But many segments were shredded and sold as a building material after 1989. Some pieces landed in the garbage.

In total, 241 parts of the wall have been placed in 146 locations around the world, according to the Federal Foundation, of which 57 are in the United States.

A special sale took place in the summer of 1990, when five Soviet artists painted 100 small concrete slabs and sold them for several hundreds of thousands of dollars to a collector in the US.

A wall for artists

Often pieces of the wall are given away as symbolic presents, such as the segment in the garden of the UN headquarters in New York. Just recently five wall segments went to South Korea, Elmar Prost, director of Berlin building materials company Klösters told DW.

Klösters bought 164 wall segments a few years ago and made them available to artists and amateur painters as a stone canvas for a small fee. A series of Nobel laureates, painted by the Spanish artist Victor Landeta, came about in this way. Landeta is currently looking for a buyer for his series.

Trust rather then guarantee

The more time that passes since the fall of the Berlin Wall, the more pressing the question of authenticity becomes. "The sale of wall parts is ultimately a matter of trust," Berlin Wall expert Ronny Heidenreich told DW.

Whether the fingernail-sized crumbs are genuine can no longer be confirmed, making reliability an important factor in the business. Gerhard Sälter of the Berlin Wall Memorial says he is particularly suspicious of colorfully painted wall parts, which sell better than their grey counterparts.

"I suspect that most parts of the wall that we can buy as tourists have been painted afterwards," he estimated.

'You don't have to buy them'

Wilbert Giebel is relaxed when it comes to doubts about the authenticity of his wall pieces. "I personally have never heard of a fake wall part being sold," he said, adding, "You do not have to buy them."

But people do buy them. Interest is especially high in the US, "because the wall expresses the German desire for freedom," said Giebel.