There's more to what makes a wine expensive than just the materials that made the wine. Sure, a $100 wine is much more expensive to make than a $10 wine. But is there such a big gap between a $100 wine and a $100,000 wine? What makes the world's most expensive wines so expensive?

Outside of the cost of production, there are a number of things that send wine prices skyrocketing. Prestige and collectability are the big two, with things like age, scarcity, and good old-fashioned trendiness feeding this.

On top of this, wines that get very high prices also often have a novelty factor that is only tangentially connected to the wine itself, distorting the idea of what makes wines expensive. The idea of the world's most expensive wine is almost impossible to quantify, as so much of the time, it isn't the wine's fault that it's so expensive.

Prestige is the key intangible when it comes to wine prices. California's State Highway 29 runs through some of the most expensive viticultural land on the planet, passing some of the most famous and lucrative wine brands along the way. Appellations like Rutherford and Yountville add value to wines, but it's names like Screaming Eagle that really get juices flowing. To buy this wine directly from the winery, you need to get onto the waiting list – some 5000 people and several years long – in order to be able to buy a scant three bottles.

In fact, many of California's most famous and exclusive wineries, including Harlan Estate and Sine Qua Non, have these enormous waiting lists that limit distribution to just a lucky few. As a result, a lot of top Californian wines are bought and sold through auction houses, where getting record prices for wines is all in a day’s work.

"An auction does a good job of reinforcing certain wines as very high-end luxury products," said Charles Antin, a senior wine specialist and auctioneer at Zachy's Wine Auctions in New York. Auctions and prestige are inextricably woven together, to the point that they feed off each other – wines that attract high prices at auction gain a lot of prestige, and then go on to gain even higher prices. Some wines are made into legends by this process.

Outside of appellation and producer, Antin notes that fashion can often influence what is selling well, listing a sudden surge in prices for wines from cult Loire producer Clos Rougeard as an example: "We've sold certain bottles of Clos Rougeard for over $500 a bottle, which is atypical for a Loire Valley Cabernet Franc."

But at auction, it's provenance that really drives prices upward. "It's not unusual to see enormous prices for wines with perfect provenance," he said, listing recent sales of Vega Sicilia and Emidio Pepe wines as examples. Wine cellars from noted collectors can also see high prices.

Of course, wine lovers are not averse to a bit of novelty, and wines with unusual provenance can also find very high prices at auction. In 1998, a number of bottles of Heidsieck Champagne were salvaged from a shipwreck in the Baltic Sea, and collectors fell over themselves to get their hands on a bottle. In 1985, a bidder purchased a single bottle of Lafite Rothschild 1787 for £105,000 ($136,000), believing it to have once belonged to America's first wine enthusiast, Thomas Jefferson. This wine would have been an expensive one regardless, but the combination of vinous prestige and founding father drove the price right up.

Charity is another place where expensive wines become even more expensive, and the annual Auction Napa Valley isn't complete without some smashed records. Since its inception in 1981, the auction has raised money for local Napa charities through the sale of rare wines and even rarer experiences from Napa producers. In 2017, this amounted to a whopping $15.7 million, with the top lots fetching as much as $2 million.

"Auction Napa Valley is more of an experience – it's not just the auction itself," said Patsy McGaughy, communications director for Napa Valley Vintners. Unlike normal auctions held at the likes of Zachy's or Sotheby's, where people come with a particular lot in mind, Auction Napa Valley functions more like a party. Spirits are high, wine has been taken – and wallets are considerably looser.

"The thing about an auction – and a charity auction in particular – are the many variables," McGaughy said. "There's the obvious: is the economy doing well, what's the mood, is consumer confidence good? How are they feeling at the moment – are they having a great time, have they had a lot of wine, are they sitting with their favorite vintner or are they competing with someone on the other side of the tent?"

Lots at Auction Napa Valley tend to feature more than just wine, with producers offering up once-in-a-lifetime experiences to accompany large format bottles or vertical collections. In 2017, one of the top lots featured a range of large format bottles from Antica and Staglin Family, as well as a luxury trip to Tuscany.

"We have to present to [our audience] unique experiences or unique wine collections that are simply not available anyplace else. Those are the lots that really resonate," said McGaughy.

While these lots fetch astronomical prices, it's worth noting that the nature of the lots themselves mean that Auction Napa Valley rarely features on "most expensive" lists. Instead, the auction helps feed that magical price inflator: prestige.

"I think it's fair to say that some of Napa Valley's most sought-after brands have gained additional notoriety through their performance at Auction Napa Valley," said McGaughy.

The auction market – both commercial and charity – sees these exorbitant prices because it helps enforce a wine's collectability. Sometimes this notion of collectability can lead to an insanely high price for a wine that has no business in any most expensive list. In 2014, a bottle of Sine Qua Non Queen of Hearts rosé from the 1995 vintage sold for an unprecedented $42,780 at auction, making it the most expensive bottle of rosé ever sold – despite the fact that it was probably well past its prime.

The wine is certainly scarce – just 25 cases were made and distributed exclusively to friends and family. Winemaker Manfred Krankl told Wine-Searcher in 2014: "I think this type of wine is bought more as art than as wine. And I, for one, understand that perfectly as I am a collector and have a somewhat obsessive personality myself."

Of course, collectability – and its associated high price tag – can be manufactured, to an extent. Releasing a product in a special format in extremely limited numbers is a risky strategy, but can pay off in dividends.

At the time of its release in 2012, the Penfolds Ampoule was the most expensive 750ml bottle ever offered on the primary market, with a price tag of around $130,000. But this was no ordinary 750ml bottle. While the wine inside, a Block 42 Kalimna Cabernet Sauvignon, is prestigious enough, the bottle itself was enough of a statement to ensure the 12 bottles made were snapped up by collectors immediately.

The wine is presented in what can only be described as a piece of art. The bottle consists of two distinct pieces of glass sculpture, each made by a different glass artist, and then packaged inside a handmade wooden cabinet. It is sold with the promise that when you want to open it, Penfolds' chief winemaker Peter Gago will come to wherever you are to deliver a masterclass on the wine.

The wine's price tag is considerably more than the sum of its parts – a normal 750ml bottle of the Block 42 will run you an average of $720, and the cost of materials for the ampoule, while undoubtedly high, are unlikely to justify the price point.

Instead, the Ampoule demonstrates the value of collectability, and how it doesn't need great age, perfect scores or the prestige of the appellation to drive prices to crazy places.

The magic combination of prestige and collectability are certainly present in Wine-Searcher's reigning most expensive wine, Domaine de la Romanée-Conti's eponymous grand cru. This list is calculated using averages, and discarding outliers, in order to draw a true picture of which wines are expensive just because they are.

DRC, as it is affectionately known, has sat at the top of the monthly updated list for years, with the top 10 dominated by wines from Burgundy, with a couple of tiny-production Rieslings from the Mosel in Germany.

Because this list deals more in averages than absolutes, it excludes wines that have an unfair advantage in terms of age or novelty factor. To be included on the list, a wine must have at least four vintages available through Wine-Searcher, and at least one of those vintages must be from the last 10 years.

This eliminates wines that are bought more as art, or as Thomas Jefferson memorabilia, and instead highlights the wines that consistently achieve high prices. They aren't one-offs – these wines have enough prestige that they can find these high prices every year, arguably making them the truest representation of the world's most expensive wines.