Welcome back to the GammaDEX decentralized Ethereum token exchange. In my last article I introduced you to the exchange and showed you how to move Ether on to it and place a trade to buy some Veritaseum. This time around you’ll sell the tokens you bought and return to Ether, but you’ll place an order which someone else will (hopefully) take. This way there’s no guarantee that the tokens will be sold, but if they are you’ll avoid paying the EtherDelta fee.

Unlock your MetaMask wallet and move VERI back to the exchange

Last time you ended the tutorial by moving the VERI that you bought from the GammaDEX exchange to your wallet on MetaMask. This time, let’s go back the other way and move that VERI balance back to the exchange. This works in a very similar way to moving ETH as we did last time.

Don’t forget that you’ll need to leave some ETH in your wallet to pay gas fees. At GammaDEX we recommend you leave around 0.01 ETH.

Click MAX to deposit full VERI balance to the exchange

When using MetaMask you’ll have to approve two separate transactions to move tokens from your wallet to GammaDEX. The first, approve, grants GammaDEX the right to move the tokens on the Veritaseum smart contract. The second transaction, depositToken, does the actual move to the exchange. MetaMask can get a bit fiddly during this process and doesn’t always seem to pop up the second approval, so look for it in the MetaMask plugin if you don’t see it after granting the first approval.

MetaMask requires two approvals

The first of MetaMask’s two approvals. If the second doesn’t pop up check the extension icon in your browser.

As always with GammaDEX you’ll see on-screen notifications keeping you up to date with the state of your transactions as they are processed by the Ethereum network.

GammaDEX keeps you up to date

Place an order to sell your Veritaseum

When you place an order on GammaDEX you are inviting other users to trade with you at a price that you define. It’s a bit like being a stallholder at a market — you can go to market with your Veritaseum and invite customers to buy them from you at a price you’re happy with.

In the Order Placement box in GammaDEX you can create your sell order. Select “SELL” from the top of the box, and ORDER, just below. From here you can set a price and the amount of the token you wish to sell.

Creating an order to sell the full VERI balance which will expire in about 38 minutes

You can set the price to anything you like, but take a look at the order book to get an idea for what the market is willing to pay just now. If you enter a price too far away from the last traded price for the token GammaDEX will warn you. It’s all too easy on some exchanges to get the token and Ether amount mixed up and end up selling your token for a fraction of its true worth.

An example Fat Finger Warning, in this case trying to sell OmiseGo

The Total field is the amount of ETH that you will receive for your Veritaseum at the price asked for.

The expiry drop-down allows you to set a time limit for the order to be traded by another user. If the order has not been traded by the time specified then it will be removed from the order book. Any unsold tokens will remain with you on the exchange — nothing will be lost apart from your entry in the order book.

You specify an expiry in blocks mined on the Ethereum blockchain. One block generally takes around 10 to 20 seconds or so to mine and GammaDEX will give you an estimate for how long the order will remain in the order book based on this.

When you’re happy click on Place Sell Order. MetaMask will ask you to sign the transaction and the order will be placed.

Follow your order on the exchange

Your orders on GammaDEX are indicated in the order book with a person icon and displayed in the Open Orders grid at the bottom of the screen. The filled column in Open Orders is there to tell you how much of the order has been taken up by other users. Eventually, when the order has been completely filled it will disappear from the exchange screen.