Why Monero might be the most fungible currency in history

Monero logo

In economics the term ‘fungibility’ refers to the interchangeability of goods. One US dollar is supposedly equal to every other US dollar – holding time and place constant. Here I discuss a few goods that have been used in different societies as a medium of exchange and reflect on their fungibility or lack thereof.

Let’s start briefly with seashells, which have been used as mediums of exchange in various parts of the world. An aesthetically-appealing seashell in good condition will generally be more well-accepted than one that is ugly and worn. Seashells can therefore be said to not be fungible. A currency must maintain homogeneity to achieve fungibility. That is, one must be just like every other if it will be subjectively valued equally to all others. The same can be said for stones, beads, tin ingots, feathers and anything else of this nature that has been used as a medium of exchange.

Observations from Prisoner of War (POW) camps during WWII

RA Radford’s paper “The Economic Organisation of a P.O.W. Camp” recounts from first-hand experiences how cigarettes spontaneously emerged as a currency among Allied prisoners inside German-controlled POW camps during World War II. In Radford’s own words: “cigarettes rose from the status of a normal commodity to that of currency.” Machine-rolled cigarettes were the most widely-accepted, and hand-rolled cigarettes were more scrupulously inspected for appropriate size and weight. (As a side note, Radford also explains that “tinned milk, jam, butter, biscuits, bully, chocolate, sugar, etc.” — all included in Red Cross food parcels — were also used as mediums of exchange as were clothing and toilet requisites). Radford describes the “lively trade in all commodities,” but their prices were not quoted in one for another but rather in terms of cigarettes. Gresham’s Law (the tendency for bad money to drive out good) also came into play. Higher-quality cigarettes tended to be used for smoking — not for currency.

Fiat’s limitations

Economists will often use the US dollar as an example of a fungible good. And to an extent, it is. “A dollar is a dollar” they say. But is it? Almost everyone prefers not to accept ripped paper dollars with writing all over them. They know that the next place they would try to spend dollars in this condition may not accept them as is. Fiat paper currency also contains serial numbers, which governments use to trace their circulation. Most people would likely prefer not to receive paper currency as payment if they knew that the serial numbers had been associated with illegal activity, which could make themselves suspect to law enforcement. We also know that one of the old US 25-cent coins (‘quarters’) made of silver are worth more than their newer copper-filled counterparts — despite the fact that Uncle Sam says they’re both worth just 25-cents. The older silver quarters have additional value both as a collectors’ item and as a precious metal. Copper may have industrial value as a conductor of electricity, but its market value tends to be far below that of silver. With both paper and coin, we see that fiat currency is also not fungible.

Bitcoin’s limitations

Bitcoin’s public ledger allows for anyone in the world with an internet connection and a browser to visit websites like www.blockchain.info and be able to check the transaction history (to which addresses, from which addresses, when, and how much) as long as a wallet address is known. Newly-created coins are more valuable to most people than coins that have been spent on the darknet where drugs, weapons, counterfeit fiat currency, and a number saddening things that I will not mention are sold. People know that merchants may prefer “clean” coins. Clean coins are so-called “non-tainted” — meaning they have never been spent on the darknet or been used for illegal online gambling, etc. Even if the merchants have no preference regarding this, Bitcoin Payment Processors (BPPs) like BitPay that enable merchants to receive bitcoin as payment are rumored to disallow payments from tainted coins. For this reason, there exists such a thing as ‘mixing services,’ which allows a user to send bitcoins to it, mixes it with bitcoins from other people, then sends bitcoins back to the user. The mixing services tend to return to the users slightly less bitcoin than the users sent to the service. This allows the mixing service to earn a profit and makes tracing the bitcoins more difficult to do since adding the sums of, let’s say, two or three smaller returns in bitcoins will not equal exactly the amount that any particular user sent to the mixing service in exchange for clean coins.

Looking even more gloomy for bitcoin fungibility-wise is the relatively new emergence of more sophisticated blockchain analytics services such as Bitfury’s Crystal Pro, which intends to add a certain element of security for companies wanting to know a great deal more than just where and when bitcoins have been previously spent.

So, bitcoin is also not fungible. If it was, then mixing services would not exist, and payment processors would not disallow payments from some coins while allowing others. With bitcoin blockchain analytics services scraping the internet, collecting data about who owns particular wallets (when available) or at least which addresses belong to which online aliases, how those bitcoins are spent, etc. it furthers a market climate in which users and companies may increasingly need to be more cautious as to which bitcoins they are willing to accept as payment.

Monero enters the scene

Monero (coded as XMR) is a so-called altcoin cryptocurrency that offers complete anonymity. Transaction histories, including the balances of particular wallets, time stamps and the origin of transactions are not publicly visible for Monero in the same way that they are with bitcoin by way of its much more transparent public ledger. As such, it may be perhaps the only truly fungible currency to have ever existed. One cannot know where Monero coins have previously been spent. In order to avoid scrutiny from law enforcement, people may avoid using Monero altogether, or they may opt to stop using it after having used it previously, but this will not change the fact that each Monero coin is equal in purchasing power to that of every other. Monero coins cannot get dirty, torn, worn or broken as can seashells and fiat currency. Unless you or someone you know mined them yourself/themselves, you cannot know if they’ve been previously spent on the darknet or how old they are, but it wouldn’t matter anyway because nobody else would know when you spend them unless you told them. Monero does offer users a proof-of-payment option so that a sender can prove to a recipient that she made a particular transaction. To do this, she provides the recipient with the transaction ID and a secret transaction key. The recipient’s address is also necessary to view proof-of-payment, but the recipient has this already. Important to note here is that when viewing proof-of-payment on Monero blockchain explorers, the sender’s address is withheld along with the transaction history of the coins spent. So there is no need for the recipient to worry if the sender’s address or the coins have been used in past illicit activity. This ensures fungibility in a way that serial number-stamped fiat paper currency cannot offer.

Monero does offer a transparency option by way of a ‘viewkey.’ Every Monero address has a private viewkey associated with it, and anyone with the viewkey can view that address’s incoming transactions. For this reason, Monero is said to be “private, optionally transparent.” But by default, every Monero transaction is hidden from the world. Transacted amounts, sender and recipient addresses are obfuscated – thus ensuring its fungibility.

Zcash as a benchmark

One other cryptocurrency worth mentioning here that perhaps comes close to Monero in fungibility is Zcash (coded as ZEC). Zcash is capable of offering similar privacy to that of Monero but is for the most part used transparently. It has shielded addresses and transparent addresses as well as shielded transactions (similar to how Monero works for all transactions unless the viewkey is shared) and public transactions (similar to how bitcoin works for all transactions). The important factor here is that every Monero transaction is private by default unless a user goes out of their way to make transaction details known. Monero is therefore a truly homogeneous product, and as such it is fungible. “A Monero is a Monero.” With Zcash, transactions are optionally private. Transactions sent from shielded addresses obfuscate the sending address. Unfortunately for Zcash (strictly speaking in terms of fungibility), users must be running a full node in order to send shielded transactions. The multi-cryptocurrency Jaxx wallet, for example, is only able to send public transactions and provides no option for shielded addresses.

As part of the research that I conducted for this article, I reached out to the Zcash team to request the ratio for shielded vs. public transactions as well as the ratio for shielded addresses vs. transparent addresses. I was told that they do not share this information at this point. Zcash obviously has a lot going for it as a currency, but in terms of fungibility, it lags behind Monero.


To sum up the main points succinctly, not every seashell is equal to every other. The same can be said for cigarettes and items in Red Cross food parcels that were used as mediums of exchange in WWII POW camps. Due to transparency of bitcoin’s blockchain, this currency doesn’t survive the fungibility test either. Fiat currencies (including US dollars) for a number of reasons – including the fact that they are stamped with serial numbers – are non-fungible. Zcash could be fungible but isn’t due to the transparency of the vast majority of its transactions and the extra work and resources required to run a full node in order to send shielded transactions. But Monero seems to be a new beast altogether.

So while it is inaccurate to say that “A dollar is a dollar,” it is indeed accurate to say that “A Monero is a Monero.” Through complete privacy it achieves homogeneity, and through homogeneity it achieves fungibility.

I would like to thank the few people that provided valuable feedback for this article as it was written.

XMR: 4Ahk6KB8Rq8fmkQC75EQJQSkHAxb9HmM1Bme7gqr8P2XAPJEfHs3BuLLV4Pyb7DfrYHXefAzXAXQ1AJoTyMkipUtJL1hdrW

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Essential iPhone apps for international road warriors

“Work smarter, not harder.”
-Author unkown

For the very fortunate breed of travelers that finds him or herself in one country after another on a regular basis, it is essential to make the best use of technology in order to maximize efficiency. I have spent the past couple of years exploring the best iPhone apps to automate my life. For me, the apps listed here below are the bare minimum to keep my life as an international traveler moving smoothly.


Priority Pass

This app is only useful for paying customers of Priority Pass. Priority Pass is a company that allows its customers to use airport lounges around the world – no matter which airline they are flying on. If you fly to the same places all the time using the same airline, you might be better off paying the airline for access to its own lounges. However, if you find yourself flying on a multitude of airlines around the world and do not wish to spend your 8-hour layovers waiting at the gate or in a food court somewhere, you will want Priority Pass. Trust me; it’s beautiful.

With the Priority Pass app, you can push the “Find Nearest Lounge” button, and the app uses your iPhone’s GPS to find the lounges that you have access to at the particular airport that you are at. I’ve been in situations in which I found myself at smaller regional airports in countries like Brazil and China. It didn’t matter! Priority Pass still had lounges for me to use in those airports!

Here is a link to 10% off your first year of Priority Pass – no matter which membership plan you choose.


CultureGPS Professional

If you are among the rare breed of culture warriors out there, you should already be aware of Professor Geert Hofstede’s work on the dimensions of national cultures. For international businessmen and businesswomen, the Hofstede index is an indispensable resource. It breaks down cultures of many countries around the world into the following dimensions: Power Distance Index (PDI), Individualism versus Collectivism (IDV), Masculinity versus Femininity (MAS), Uncertainty Avoidance Index (UAI) and Long-Term Avoidance (LTO). Newer dimensions added to the Hofstede index (not in this app, unfortunately) are: Pragmatic versus Normative (PRA) and Indulgence versus Restraint (IND).

Let’s say, for example, that you are an account manager for the company your work for and will be meeting with a new buyer of your company’s product in Country-X for the first time. The purpose of the meeting is to negotiate future terms between both companies. If Country-X happens to score high on Hofstede’s Power Distance Index (PDI) dimension, you can expect that it is less likely that you will have access to the owner or other high-level decision-makers of the foreign company (since you are an account manager – a lower position than an owner in corporate hierarchy). This is cultural intelligence at its finest. If you frequently travel to a diverse range of countries (geographically, linguistically, ethnically, religiously) I highly recommend this app!

There are many books that I could also recommend here that have been instrumental in my personal development in cultural intelligence, but if I had to recommend only three they would be the three below. In some ways they overlap with information, however, the countries they cover vary. So if you travel just about everywhere you will find it beneficial to keep all three in your library. The first two books below dedicate each individual chapter to the cultural and business practices of specific countries (every chapter is a different country). The latter concentrates more on cultural and business practices of geographical clusters (Middle East and North Africa, for example) as well as provides specific information for a few key countries.

  1. Kiss, Bow, or Shake Hands by Terri Morrison
  2. Kiss, Bow, or Shake Hands, Sales and Marketing: The Essential Cultural Guide—From Presentations and Promotions to Communicating and Closing by Terri Morrison
  3. How to Negotiate Anything with Anyone Anywhere Around the World by Frank Acuff


The World Clock

I tried at least three of the world clock apps before falling in love with this one by Orlin Kolev. The World Clock is able to not only track the time zones in the individual cities of your choosing, but it even works with your Google Calendar.

Let’s say that on a particular date and time you have scheduled a conference call with a customer in Ghana, but on that date you will be in Bangkok, Thailand. With The World Clock you can enter the date and time that you told your customer in Ghana you would call him, and the app shows you what date and time the appointment will be in Bangkok. You can then choose to setup a Google Calendar event right from the app along with alert reminders so you don’t forget to actually make the call!

Note: While gathering the necessary links and information to produce this blog post I ran into a competing app that looks quite good called World Clock Pro.



Documents can open all of your Microsoft Word and Excel documents and allows you to edit them, organize them in folders, send them as email attachments, back them up on Dropbox and more. It can also open other major file formats, such as PDF. It’s simple. Without it, an iPhone is limited to the Notes app, which is as plain as Microsoft Notepad.

With this app I am able to work on the go.




Currency Converter HD

I experimented with two or three competing apps before choosing this one. The first one I tried was by XE, only because XE is popular in FOREX. Unfortunately, the XE app bombards the user with ads and does not have some of the other options I appreciate from Currency Converter HD.

Currency Converter HD’s nifty calculator also saves you from having to open the iPhone’s Calculator app in order to do a calculation after converting the currency. Like other competing currency exchange apps, this one updates the latest conversions frequently and automatically as long as your phone is connected to the internet and the app is running.


American Airlines

When I am flying with American Airlines or other member airlines of the oneworld alliance, I often open this app as soon as the plane lands to see if my next flight’s departing time or gate number has changed. (The app can notify you if there are flight changes!)

Using airline apps like this one saves you the time and hassle of having to locate the monitors in the airport with all the flight schedules listed.




Delta Airlines

When I am flying with Delta Airlines or other member airlines of the SkyTeam alliance, I sometimes open this app as soon as the plane lands to see if my next flight’s departing time or gate number has changed. (The app can notify you if there are flight changes!)

Using airline apps like this one saves you the time and hassle of having to locate the monitors in the airport with all the flight schedules listed.




United Airlines

When I am flying with United Airlines or other member airlines of StarAlliance, I sometimes open this app as soon as the plane lands to see if my next flight’s departing time or gate number has changed. (The app can notify you if there are flight changes!)

Using airline apps like this one saves you the time and hassle of having to locate the monitors in the airport with all the flight schedules listed.




Frequent Flyer Miles Tracker

This is the app I use to store my frequent flyer mileage numbers for each airline that I have an account with. If you are at the check-in counter at the airport and for whatever reason do not have your airline priority membership card readily available, just open this app so that the airline official can check you in with your frequent flyer mileage number.




National Geographic World Atlas

I discovered this app while researching for this blog post and was looking for a better app to recommend than the world factbook that I had been using. I am impressed with this one.

When connected to the internet the apps can zoom in even closer. Other than maps, it has information on each country such as: languages spoken, economic and government data, major holidays, religions practiced, information on major cities within each country and more. It even has a currency converter tool (but no calculator built in). I’m sold!



Audiobooks from Audible

If I had to choose only one app it would be this one. How else am I supposed to pass the time?

Read more here for my thoughts on audiobooks.







Athan Pro – Prayer Timings and Tracking

If you do business in the Muslim World, you’ll want this app. It is always helpful to know when the prayer times are in each country so that you can setup appointments without interruption. I once had an international guest from Morocco visit me in the USA. He told me that on Friday of that week he wanted to go to the local mosque and pray. I opened the Athan Pro app, typed in the local zip code, and I instantly had all the prayer times at my fingertips. Later I called the mosque to verify that the time was correct. It was spot on.



Skype WiFi

Sometimes you’re in an international airport, and all the available WIFI signals are either blocked, or to use them, you would have to go through the annoying hassle of entering your credit card number and personal information. Skype WiFi bypasses all of that. If you have a Skype account (which you should!) you can simply use your Skype credit to connect to connect to the WIFI networks that require payment. Connection times are in 30-minute intervals.




Google Translate

If you’re an international road warrior or at least speak a foreign language you are probably already aware of this one. Google Translate is able to translate from any one language to another with more than sixty to choose from. The app requires a connection to the internet.





Michaelis Moderno Dicionário de Português e Inglês

I realize that not everyone speaks a combination of Portuguese and English. This dictionary app represents whatever advanced dictionary app you would need. If you find yourself often conversing between German and Japanese and you do not speak both at a native level, then I suggest keeping an advanced dictionary around such as this one.

I recommend the Michaelis Moderno dictionary apps. They are very complete and even come with other features, such as being able to see a full breakdown of conjugations for any verb. For that reason, this particular app is sold for $29.99. It was well worth what I paid. Michaelis Moderno dictionary apps require no connection to the internet and give all possible alternative translations for each word; Google Translate, by contrast, only gives a single, best guess translation.



This is the #1 app that you should have for all communication while abroad. You can call anywhere in the world for free (if the person you’re calling has a Skype account) and can call telephones for only a few cents per minute.

But you’ve probably been using Skype for years already, so keep reading…






To me, Viber is just another app for chatting since it has all the same major features as Skype and WhatsApp. But if you have business partners and customers around the world, at least some of them will be using it, so it is very useful to have.






WhatsApp Messenger

WhatsApp is just like Viber. If you’ve got a wide range of friends and business contacts, you should probably have this app too.








No doubt you’ll hear music while abroad, and you’ll want to identify the artist and song title. SoundHound is a free app that can listen to the music in the background wherever you are and then look up the artist and song title for you. If you have no connection to the internet where you are, no worries… SoundHound can temporarily store the recorded audio clip and try to locate the song for you later once you’ve reestablished an internet connection.

Full disclosure: Although SoundHound has access to a giant database of all sorts of music, I’ve noticed the app is better at identifying more mainstream music. Don’t be surprised if it cannot recognize, let’s say, a Turkish song that hasn’t yet made it to international radio stations.


I also refer frequently to the following resources:

  1. Airline alliance Wiki page – Since I generally purchase flights from budget travel websites, I fly a wide range of airlines from all three major alliances and some others that do not belong to any alliance. When purchasing my flights, it is important to enter in the frequent flyer number of the airline that 1) is a common member airline of the same alliance of the particular flight in question, and 2) is the airline that I track my frequent flyer miles with for that alliance. To maximize your frequent flyer miles (assuming you want free upgrades, flights, etc.) you are going to want to try to make sure that as many of your flights as possible are on member airlines of one of the three major alliances: Star Alliance, SkyTeam, and oneworld. This Wiki article is the only single place on the WWW that I’ve found that keeps them so well-organized. I’ve noticed that the article also gets updated often when airlines move from one alliance to another.
  2. Air Miles Calculator – Enter in just about any two or more airports, and this website will tell you how many frequent flyer miles you should accrue. The website does not account for multipliers, so if you have elite status on a particular airline, you might earn something like 1.25 or 1.5 frequent flyer miles per actual “butt in seat” mile that the Air Miles Calculator website tries to calculate for.


*If you know of an app that deserves to be on this list you may leave a comment below or email me at emileaphaneuf (at) gmail.com. I am also looking to produce an equivalent post to this one for Android and Blackberry. If you have international travel experience and a number of favorite apps for smooth travel for either the Android or Blackberry platforms you may also contact me. 


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