How does the steam market work for different currencies?

I searched on web and read many article but i still cant understand How do the steam market and its currency converter work? I also wonder why there are so many spikes in some lower valued items like this.

I came across an interesting result when i give an order then removed it. Here is what happened and the screenshots in order.

I gave 10 order for 0.20 TRY and i show it is converted to 0.05$ but it says 0.3$ in activity. (Real currency is 0.20 TRY = 0.037 USD ~ 0.04$) Both 0.20 try and 0.05$ was highest bid on the market.

I thought activity might use different converter and its just for info this might not effect anything but it looks like its not because i found one more thing. I gave 10 order for 0.36TRY another card and it highest bid order like before in my currency i was waiting to be listed for 0.08$ but it is listed for 0.06$.

There was only 1 order for 0.36TRY and 1 order for 0.08$ on the market before i gave order.

I show 11 order 0.36TRY , 1 order for 0.08$ 10 order for 0.06$ after gave my order.

I would understand if the difference was 0.01$ and i would think its rounding issue but it looks like it not. Does anyone have an opinion why that happens? You can try it in your currency and we can discuss.

Note: I did not use steam addons to convert currencies i used chrome incognito tab to see prices in dollar.