How to horizontally center an item in Material UI grid item?

Two seconds later... I solved this through some simple CSS:

<Grid item xs={4} style={{textAlign: "center"}}>

If there is another approach that is somehow more "correct", please feel free to post another answer.

 <Grid container  className = {classes.root} align = "center" justify = "center" alignItems = "center"  >
            <Grid item xs = {false} sm = {4} md = {6}>

            <Grid item xs = {12} sm = {4} md = {6}>

        </Grid>`enter code here`

This is the correct way:

<Grid container item xs={4} justify="center">

if container property is set to true the component will have the flex container behavior.

Grid API