What are the differences between first tier and second tier securities?

First tier securities, often referred to as "blue-chip" stocks, are high-quality investments typically issued by well-established companies with a strong financial performance and stable earnings. They are generally more liquid and less volatile, making them safer for investors. Second tier securities, on the other hand, include mid-cap or smaller companies that may offer higher growth potential but come with increased risk and volatility. These securities may have less market liquidity and are often less widely followed by analysts.