This is a very technical topic, so it may not make sense to read it unless you are involved…

It is common to use ETH (Ethereum) for minting (the cost of converting digital data to NFT = gas) to exchange NFT art, but there are high fees depending on the time. In recent years, it costs about 7-9,000 yen per piece.

So, using Polygon as a side chain (the main chain is Ether), gas is free.

The NFT art itself is bought and sold in a currency called ETH, so if all the artwork and gas and other fees are done in ETH, the buying and selling is smooth, but there is a possibility of lost funds when the ETH is sent to Polygon and out of Polygon.

If you send the Polygon version of ETH directly to the exchanges Binance or coincheck, you will self-GOX (lose the virtual currency in your possession due to your own carelessness).

Although it looks like the same ETH, Polygon’s version of ETH is completely different from Ethereum Mainnet’s ETH.

Well, let me preface this by saying that I read an article about SBI Art Auction holding Japan’s first NFT art auction, “NFT in the History of Contemporary Art,” at Hillside Forum in Daikanyama, Tokyo.

In that piece, an acquaintance of mine, Sputniko! I learned about Mr. Kurokawa’s work from his website.
The price is so high that SBI Auction estimates the expected price of this piece to be 3-5 million yen, and I wondered if it was not worth the risk to the participants by skimping on the gas fee of less than 10,000 yen.

https://www.sbiartauction.co.jp/auction/detail/101/151