I have a rich text field on the opportunity that I need to populate with various peices of data on the opportunity. I have two main issues:

1. I am able to do this, but with only a single data type at a time. I can not seem to figure out how to combine all three lists into a single list.  Here is what I have so far.

2. My \n is not making the next line item go on to a new line down.

trigger OpportunityProuctCopytoHiddenField on Opportunity (before insert, before update) {
for(Opportunity t:trigger.new)
      {
        List<String> NewList= new List<String>();
        List<Decimal> NewList2= new List<Decimal>();
        List<Datetime> NewList3= new List<Datetime>();
        if (t.HasOpportunityLineItem == true)
        {
             for(OpportunityLineItem OpLine: [SELECT CreatedBy.Name, Quantity, TotalPrice, LastModifiedDate, PriceBookEntry.Name, UnitPrice, ID FROM OpportunityLineItem WHERE OpportunityId =:t.Id] )
            {
                NewList.add(OpLine.PriceBookEntry.Name);
                NewList.add(' has been authorized by ');
                NewList2.add(OpLine.Quantity);
                NewList.add(OpLine.CreatedBy.Name);
                NewList.add('and the transation has been logged into the record id: ');
                NewList.add(OpLine.ID);
                NewList.add(' on');
                NewList3.add(OpLine.LastModifiedDate);
                            }
            for(String c : NewList){
            t.Hidden_Products__c = t.Hidden_Products__c + c + '\n';
            }
        }
    }
}

And i am pretty sure what I am missing is somewhere around:

            for(String c : NewList){
            t.Hidden_Products__c = t.Hidden_Products__c + c + '\n';